Revert "Revert "genalloc: stop crashing the system when destroying a pool""

This reverts commit a1f76167e2c924ee65b1663344a7ffa705fdc15b.
msm: mdss: Clear the previous state of pipe during SOLID_FILL

Clear the previous state of pipe when it is being used in SOLID_FILL
operation to prevent wrong register configuration. For ex: Use case
when DMA pipe was used in BLOCK mode in previous frame, then it is
being used in LINE mode for SOLID_FILL operation in current frame.

CRs-Fixed: 655993
Change-Id: I0ed257276428b96c10a92457a16df4dfdc42c1f8
Signed-off-by: Sushil Chauhan <sushilchauhan@codeaurora.org>