minui: remove overlay support for MDSS_V5 for now and add support for MDP_V3_0_4.

As well fix wrong detection of MDP_V3_0_3

MDSS_V5 support disabled for now till we integrated into the recovery native
support for mdss_fb_split node via sys path or directly from the driver
(see qcom display mdp_version.cpp)

PS:
- cleanup like suggested by Josue

Change-Id: I4813230c459a6c1718e3cb3bb80467fc88237f21