defconfig: 8916: disable forced 4K allocation/mapping

Forced 4K allocation and mapping for SMMU incurs significant
perf drop. Disable this config until required for perf
testing again.

Change-Id: I5fa90e8a14870ef32bd6f509be9ca1070961a3ae
Signed-off-by: Chintan Pandya <cpandya@codeaurora.org>