drm/msm: rename MSM drm platform driver's name into msm_drm

Before this change, the driver's name was defined as "msm". This
definition conflicts with another MSM driver in the downstream
kernel (camera_v2).
To avoid such conflict (kernel crash), the msm drm driver's name
is changed to "msm_drm", which is also a bit more explicit than
the previous definition.

Conflicts:
	drivers/gpu/drm/msm/msm_drv.c

Change-Id: Idc3e9d3e5d2b04e78e0b7665b7036c07f94d4413
Signed-off-by: Stephane Viau <sviau@codeaurora.org>
[cip@codeaurora.org: Also change name of drm driver
and workqueue from "msm" to "msm_drm"]
Signed-off-by: Clarence Ip <cip@codeaurora.org>
Signed-off-by: Dhaval Patel <pdhaval@codeaurora.org>
[narendram@codeaurora.org: resolve conflict msm_drv.c]
Signed-off-by: Narendra Muppalla <narendram@codeaurora.org>