CONFIG_GENERIC_PINCTRL_GROUPS must be selected in order for
struct group_desc to be defined in pinctrl/core.h.

Add the missing select line to CONFIG_PINCTRL_WPCM450.
Reported-by: kernel test robot <lkp@intel.com>
Fixes: a1d1e0e3 ("pinctrl: nuvoton: Add driver for WPCM450")
Signed-off-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net>
Link: https://lore.kernel.org/r/20220317114413.1418484-1-j.neuschaefer@gmx.netSigned-off-by: Linus Walleij <linus.walleij@linaro.org>