msm: remote_spinlock: Support multiplatform

Upstream prefers existing drivers be converted to support multiplatform
kernels.  This requires drivers to be located in generic functionality
directories instead of specific mach directories.

Move the remote-spinlock driver to the drivers/hwspinlock location to
support multiplatform.

Change-Id: Ibbc6046ab177b62a5a79cba7f5752685470c4ebb
Signed-off-by: Jeffrey Hugo <jhugo@codeaurora.org>