pinctrl: core: Fix kernel doc string for pin_get_name()

pinctrl: core: Fix kernel doc string for pin_get_name()

The kernel doc string mistakenly advertises the pin_get_name_from_id().
Fix it, otherwise kernel doc validator is not happy:

.../core.c:168: warning: expecting prototype for pin_get_name_from_id(). Prototype was for pin_get_name() instead

Fixes: 9d4a21d8c4e1 ("pinctrl: show pin name for pingroups in sysfs")
Cc: Dong Aisheng <dong.aisheng@linaro.org>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20210415123521.86894-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>