ARM: OMAP4+: Clean up the pmic code

The pmic code is duplicated for OMAP 4 and 5.
Instead move the data to Soc specific place and
share the code.

Signed-off-by: R Sricharan <r.sricharan@ti.com>
Signed-off-by: Lokesh Vutla <lokeshvutla@ti.com>
Reviewed-by: Tom Rini <trini@ti.com>