regulator: fixed: Fix incorrectly formatted kerneldoc "Return" section

regulator: fixed: Fix incorrectly formatted kerneldoc "Return" section

kernel-doc complains about missing "Return" section for kerneldoc of
of_get_fixed_voltage_config(). The kerneldoc has a description
about the return values, just not in the format kernel-doc wants.

Convert it to use the proper "Return:" section header. The existing
description have been reworded and moved around to fit the grammar and
formatting.

Signed-off-by: Chen-Yu Tsai <wenst@chromium.org>
Reported-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://patch.msgid.link/20240829085131.1361701-7-wenst@chromium.org
Signed-off-by: Mark Brown <broonie@kernel.org>