ARM: dts: msm: Remove increase rmtfs buffer size in 8917

This reverts 'commit 1ee2b88d04c9 ("ARM: dts: msm: Increase rmtfs buffer
size in 8917")'.As it could be high risk to pick it up
post commercialization.

Change-Id: I52a4d8248034abeccfb92a49c1e4a5c292dff331
Signed-off-by: Pavan Anamula <pavana@codeaurora.org>