pinctrl: amd: Use PINCTRL_PINGROUP to manage pingroups

AMD pingroup can be extended to support multi-function pins.
Hence use PINCTRL_PINGROUP to manage and represent larger
number of pingroups inline.

Signed-off-by: Basavaraj Natikar <Basavaraj.Natikar@amd.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20220601152900.1012813-4-Basavaraj.Natikar@amd.com


Signed-off-by: Linus Walleij <linus.walleij@linaro.org>