msm_fb: display: add mdp version info for later mdp h/w

fbtest needs to get the correct mdp version number, but now only the
version up to mdp4.0 is returned. Add the latest mdp version up to
4.4.

Change-Id: If1ff302bb4a02ed13bb4dcabcb933fd5adfbec6d
Signed-off-by: Huaibin Yang <huaibiny@codeaurora.org>
Signed-off-by: Siddhartha Agrawal <agrawals@codeaurora.org>