defconfig: apq8084: Disable non-secure OCMEM

The secure environment is now responsible for some aspects of
OCMEM management. Disable the config to have Linux do this management.

Change-Id: Ic14a5b54cc487c0d0a3d40362a3823a96ea1d3c8
Signed-off-by: Laura Abbott <lauraa@codeaurora.org>