gpio: tangier: unexport suspend/resume handles

Unexport suspend/resume handles for the lack of external users and while
at it, make them static, so that they can be discarded by the compiler
if not used (CONFIG_PM_SLEEP=n).

Signed-off-by: Raag Jadav <raag.jadav@intel.com>
Link: https://lore.kernel.org/r/20231113131600.10828-4-raag.jadav@intel.com


Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>