msm: avs: move avs driver to a new location in kernel

This patch moves the AVS driver to appropriate directory
in the kernel tree (i.e drivers/power/avs).

Change-Id: I9d393a6f4e6baf5c9a1b30b60a6e638992deb6d3
Signed-off-by: Murali Nalajala <mnalajal@codeaurora.org>