pinctrl: realtek: Support system suspend and resume

pinctrl: realtek: Support system suspend and resume

Add system suspend and resume capabilities to the common Realtek pinctrl
library. This enables saving and restoring pin configurations during the
noirq phase for SoCs that define register ranges.

Signed-off-by: Tzuyi Chang <tychang@realtek.com>
Co-developed-by: Yu-Chun Lin <eleanor.lin@realtek.com>
Signed-off-by: Yu-Chun Lin <eleanor.lin@realtek.com>
Signed-off-by: Linus Walleij <linusw@kernel.org>