mdss: display: add command mode mdp fifo underflow recovery

At command mode, mdp underflow can not be recovered but cause
mdp to hang up. Add mdp underflow recovery mechanism  when mdp
underflow detected.

Change-Id: I26fc64005ac247372257aa126f2c8c0076925bb9
Signed-off-by: Kuogee Hsieh <khsieh@codeaurora.org>
Signed-off-by: Sree Sesha Aravind Vadrevu <svadrevu@codeaurora.org>
Makefile: Enable ccache
fat: limit the number of error prints

Use fat_fs_error_ratelimit instead of fat_fs_error so as to
avoid large number of prints.

Change-Id: I2e21e6bd0c8e7e79d3ced9c213668c405fd6260d
Signed-off-by: Asutosh Das <asutoshd@codeaurora.org>
Signed-off-by: Manish Kumar <manishku@codeaurora.org>