msm: spm: move SPM drivers to machine independent directory

This moves spm-v2.c and spm_devices.c drivers from mach-msm
directory to machine independent location in a kernel tree.

Change-Id: I1b79838b678e13c1ab46bec4e5d816dc634cd29e
Signed-off-by: Murali Nalajala <mnalajal@codeaurora.org>