[6/7] docs: update some straggling Documentation/arm references

The Arm documentation has moved to Documentation/arch/arm; update the
last remaining references to match.

Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Cc: Chen-Yu Tsai <wens@csie.org>
Cc: Jernej Skrabec <jernej.skrabec@gmail.com>
Cc: Samuel Holland <samuel@sholland.org>
Cc: Thierry Reding <thierry.reding@gmail.com>
Cc: "Uwe Kleine-König" <u.kleine-koenig@pengutronix.de>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: linux-input@vger.kernel.org
Cc: linux-sunxi@lists.linux.dev
Cc: linux-pwm@vger.kernel.org
Cc: linux-serial@vger.kernel.org
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
---
 MAINTAINERS                          | 6 +++---
 drivers/input/touchscreen/sun4i-ts.c | 2 +-
 drivers/pwm/pwm-atmel.c              | 2 +-
 drivers/pwm/pwm-pxa.c                | 2 +-
 drivers/tty/serial/Kconfig           | 4 ++--
 5 files changed, 8 insertions(+), 8 deletions(-)

Hi Jonathan,

kernel test robot noticed the following build warnings:

[auto build test WARNING on linus/master]
[also build test WARNING on v6.4-rc2 next-20230519]
[cannot apply to sunxi/sunxi/for-next arm64/for-next/core thierry-reding-pwm/for-next]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]

url:    https://github.com/intel-lab-lkp/linux/commits/Jonathan-Corbet/arm-docs-Move-Arm-documentation-to-Documentation-arch/20230520-005124
base:   linus/master
patch link:    https://lore.kernel.org/r/20230519164607.38845-7-corbet%40lwn.net
patch subject: [PATCH 6/7] docs: update some straggling Documentation/arm references
reproduce:
        # https://github.com/intel-lab-lkp/linux/commit/3c9885f2702a3319156cfbacedfca658e726213b
        git remote add linux-review https://github.com/intel-lab-lkp/linux
        git fetch --no-tags linux-review Jonathan-Corbet/arm-docs-Move-Arm-documentation-to-Documentation-arch/20230520-005124
        git checkout 3c9885f2702a3319156cfbacedfca658e726213b
        make menuconfig
        # enable CONFIG_COMPILE_TEST, CONFIG_WARN_MISSING_DOCUMENTS, CONFIG_WARN_ABI_ERRORS
        make htmldocs

If you fix the issue, kindly add following tag where applicable
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202305201023.2DYXmdv3-lkp@intel.com/

All warnings (new ones prefixed by >>):

>> Warning: MAINTAINERS references a file that doesn't exist: Documentation/arch/arm64/

kernel test robot <lkp@intel.com> writes:

> Hi Jonathan,
>
> kernel test robot noticed the following build warnings:
>
> [auto build test WARNING on linus/master]
> [also build test WARNING on v6.4-rc2 next-20230519]
> [cannot apply to sunxi/sunxi/for-next arm64/for-next/core thierry-reding-pwm/for-next]
> [If your patch is applied to the wrong git tree, kindly drop us a note.
> And when submitting patch, we suggest to use '--base' as documented in
> https://git-scm.com/docs/git-format-patch#_base_tree_information]
>
> url:    https://github.com/intel-lab-lkp/linux/commits/Jonathan-Corbet/arm-docs-Move-Arm-documentation-to-Documentation-arch/20230520-005124
> base:   linus/master
> patch link:    https://lore.kernel.org/r/20230519164607.38845-7-corbet%40lwn.net
> patch subject: [PATCH 6/7] docs: update some straggling Documentation/arm references
> reproduce:
>         # https://github.com/intel-lab-lkp/linux/commit/3c9885f2702a3319156cfbacedfca658e726213b
>         git remote add linux-review https://github.com/intel-lab-lkp/linux
>         git fetch --no-tags linux-review Jonathan-Corbet/arm-docs-Move-Arm-documentation-to-Documentation-arch/20230520-005124
>         git checkout 3c9885f2702a3319156cfbacedfca658e726213b
>         make menuconfig
>         # enable CONFIG_COMPILE_TEST, CONFIG_WARN_MISSING_DOCUMENTS, CONFIG_WARN_ABI_ERRORS
>         make htmldocs
>
> If you fix the issue, kindly add following tag where applicable
> | Reported-by: kernel test robot <lkp@intel.com>
> | Closes: https://lore.kernel.org/oe-kbuild-all/202305201023.2DYXmdv3-lkp@intel.com/
>
> All warnings (new ones prefixed by >>):
>
>>> Warning: MAINTAINERS references a file that doesn't exist: Documentation/arch/arm64/

Sigh...obviously this hunk:

 L:	linux-arm-kernel@lists.infradead.org (moderated for non-subscribers)
 S:	Maintained
 T:	git git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git
-F:	Documentation/arm64/
+F:	Documentation/arch/arm64/
 F:	arch/arm64/
 F:	tools/testing/selftests/arm64/

...got a bit ahead of the game.  I'll take that one out, sorry for the
noise.

jon