msm: smem_log: Support multiplatform

Convert to support multiplatform kernels. This requires drivers to be
located in generic functionality directories instead of specific mach
directories.

Move the smem_logging driver to the drivers/soc/qcom location to support
multiplatform.

Change-Id: I735ecf723c55147528f7593d3a6afac053410473
Signed-off-by: Arun Kumar Neelakantam <aneela@codeaurora.org>