Now that omap_test_timeout is only accessible from mach-omap2/,
introduce a similar function for SR.

This change makes the SmartReflex implementation ready for the move
to drivers/.
Signed-off-by: NJean Pihet <j-pihet@ti.com>
Signed-off-by: NJ Keerthy <j-keerthy@ti.com>
Reviewed-by: NKevin Hilman <khilman@ti.com>
Signed-off-by: NKevin Hilman <khilman@ti.com>