pinctrl: samsung: add support for eint_fltcon_offset

pinctrl: samsung: add support for eint_fltcon_offset

On gs101 SoC the fltcon0 (filter configuration 0) offset isn't at a
fixed offset like previous SoCs as the fltcon1 register only exists when
there are more than 4 pins in the bank.

Add a eint_fltcon_offset and new GS101_PIN_BANK_EINT* macros that take
an additional fltcon_offs variable.

This can then be used in suspend/resume callbacks to save and restore
the fltcon0 and fltcon1 registers.

Fixes: 4a8be01a1a7a ("pinctrl: samsung: Add gs101 SoC pinctrl configuration")
Cc: stable@vger.kernel.org
Reviewed-by: André Draszik <andre.draszik@linaro.org>
Signed-off-by: Peter Griffin <peter.griffin@linaro.org>
Link: https://lore.kernel.org/r/20250307-pinctrl-fltcon-suspend-v4-1-2d775e486036@linaro.org
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>