msm: msm_bus: introduce msm bus api stubs

Initial port of msm bus APIs into new kernel version from msm-4.4,
<f600d8b9ec91f>("msm-core: Move get_user out side critical section")

Change-Id: If2122b3dc508d87e67bc8bd0ca2d4ebec1e0d758
Signed-off-by: David Dai <daidavid1@codeaurora.org>
3 files changed