fbdev: msm: try recovering from PP timeout without panic

Driver dumps mdp register and xlog as soon as pingpong
timeout occurs. It is possible to recover device while
waiting for TE signal, so call panic if pingpong timeout
happens for 10 consecutive frames.

Change-Id: I1661b21b3179f77a0a8daa8d2cde2115c7a38f5e
Signed-off-by: Raghavendra Ambadas <rambad@codeaurora.org>