drm/msm: move mdp4 -> mdp/mdp4

There are some little bits and pieces that mdp4 and mdp5 can share, so
move things around so that we can have both in a common parent
directory.

Signed-off-by: Rob Clark <robdclark@gmail.com>

diff --cc drivers/gpu/drm/msm/Makefile
Simple merge

diff --cc drivers/gpu/drm/msm/mdp/mdp4/mdp4.xml.h
Simple merge

diff --cc drivers/gpu/drm/msm/mdp/mdp4/mdp4_crtc.c
Simple merge

diff --cc drivers/gpu/drm/msm/mdp/mdp4/mdp4_dtv_encoder.c
Simple merge

diff --cc drivers/gpu/drm/msm/mdp/mdp4/mdp4_format.c
Simple merge

diff --cc drivers/gpu/drm/msm/mdp/mdp4/mdp4_irq.c
Simple merge

diff --cc drivers/gpu/drm/msm/mdp/mdp4/mdp4_kms.c
Simple merge

diff --cc drivers/gpu/drm/msm/mdp/mdp4/mdp4_kms.h
Simple merge

diff --cc drivers/gpu/drm/msm/mdp/mdp4/mdp4_plane.c
Simple merge