defconfig: Enable BALANCE_ANON_FILE_RECLAIM for 8916 64bit

BALANCE_ANON_FILE_RECLAIM helps in improving headroom by
swapping anon memory earlier. This helps saving more memory
and helps overall system performance when ZRAM is enabled.
Enable this config on 64 bit targets for performance reasons.

Change-Id: Ib72a25457749077853582414bb504adfface3da9
Signed-off-by: Susheel Khiani <skhiani@codeaurora.org>