defconfig : enable quota feature for SDM450

The recent Android O upgrade mandates disk quota feature to be enabled
by default on /data. Hence, enable the required kernel config options to
support the same

Change-Id: I7f0778f7cf27c0c506979c989c708f5ddcf18d50
Signed-off-by: Ankit Jain <jankit@codeaurora.org>