The smartreflex modules belong to an ALWON_FCLK clock domain that
does not have any SW control. The gating of that interface clock
is triggered by a transition of the WKUP clock domain to idle.

Attach both smartreflex instances on OMAP3 to the WKUP clock domain.

The missing clock domain field in srX_fck clock nodes was reported by
Kevin during the discussion about smartreflex on OMAP3:
https://patchwork.kernel.org/patch/199342/Signed-off-by: Benoit Cousson <b-cousson@ti.com>
Signed-off-by: Paul Walmsley <paul@pwsan.com>
Cc: Kevin Hilman <khilman@deeprootsystems.com>