gpio/omap: remove cpu_is_omapxxxx() checks from *_runtime_resume()

Add register offsets for GPIO_IRQSTATUS_RAW_0, GPIO_IRQSTATUS_RAW_0
which are present on OMAP4+ processors. Now we can distinguish
conditions applicable to OMAP4,5 and those specific to OMAP24xx
and OMAP3xxx.

Cc: Kevin Hilman <khilman@ti.com>
Cc: Tony Lindgren <tony@atomide.com>
Cc: Santosh Shilimkar <santosh.shilimkar@ti.com>
Cc: Cousson, Benoit <b-cousson@ti.com>
Cc: Grant Likely <grant.likely@secretlab.ca>
Signed-off-by: Tarun Kanti DebBarma <tarun.kanti@ti.com>
Reviewed-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Tested-by: Govindraj.R <govindraj.raja@ti.com>
Signed-off-by: Kevin Hilman <khilman@ti.com>