3430 clock: revise SmartReflex clocks

The two SmartReflex voltage controllers on OMAP3430 have one
functional clock each.  These clocks appear to be independent of each
other.  Encode them appropriately, replacing the previous 'sr_alwon_fck'
clock.

Signed-off-by: Paul Walmsley <paul@pwsan.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>