msm: mdss: remove frame buffer allocation on 8x10

Frame buffer was used by the recovery mode.   Now,
recovery mode has been updated to use the display
overlay API for display updating, thus making
frame buffer allocation redundant.

CRs-fixed: 515447
Change-Id: I4d624d2d83c6f4815efde97250d02c8b8b7d0666
Signed-off-by: Xiaoming Zhou <zhoux@codeaurora.org>