watchdog: imx7ulp_wdt: move post_rcs_wait into struct imx_wdt_hw_feature

watchdog: imx7ulp_wdt: move post_rcs_wait into struct imx_wdt_hw_feature

Move post_rcs_wait into struct imx_wdt_hw_feature to simple code logic for
difference compatible string.

i.MX93 watchdog needn't wait 2.5 clocks after RCS is done. So needn't set
post_rcs_wait.

Signed-off-by: Frank Li <Frank.Li@nxp.com>
Signed-off-by: Alice Guo <alice.guo@nxp.com>
Reviewed-by: Ye Li <ye.li@nxp.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/20240730145610.2177627-1-Frank.Li@nxp.com
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@linux-watchdog.org>