pinctrl: actions: pinctrl-s500: Constify s500_padinfo[]

s500_padinfo[] is never modified and should be made 'const' to allow
the compiler to optimize code generation, i.e. put it in the text
section instead of the data section.

Before:
   text    data     bss     dec     hex filename
  12503    5088       0   17591    44b7 drivers/pinctrl/actions/pinctrl-s500.o

After:
   text    data     bss     dec     hex filename
  14435    3156       0   17591    44b7 drivers/pinctrl/actions/pinctrl-s500.o

Signed-off-by: Cristian Ciocaltea <cristian.ciocaltea@gmail.com>
Link: https://lore.kernel.org/r/24505deb08d050eb4ce38f186f4037d7541ea217.1605722628.git.cristian.ciocaltea@gmail.com


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