pinctrl: cy8c95x0: Rename PWMSEL to SELPWM

pinctrl: cy8c95x0: Rename PWMSEL to SELPWM

There are two registers in the hardware, one, "Select PWM",
is per-port configuration enabling PWM function instead of GPIO.
The other one is "PWM Select" is per-PWM selector to configure
PWM itself. Original code uses abbreviation of the latter
to describe the former. Rename it to follow the datasheet.

Fixes: e6cbbe42944d ("pinctrl: Add Cypress cy8c95x0 support")
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/20250203131506.3318201-5-andriy.shevchenko@linux.intel.com
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>