ARM: OMAP4: CM: move public definitions from cminst44xx.h to cm44xx.h

cminst44xx.h will be removed, thus move the public APIs to cm44xx.h header.

Signed-off-by: Tero Kristo <t-kristo@ti.com>
Acked-by: Paul Walmsley <paul@pwsan.com>
Tested-by: Nishanth Menon <nm@ti.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>