defconfig: msm: enable Linux Kernel Dump Test Tool

This feature enables to test Privilege Access Never (PAN) feature from
user space through ACCESS_USERSPACE interface supported by LKDTM.
Enable it only in debug defconfig.

Change-Id: I2723e5d8b27d1c0abcab42e9c907c3cbf6501673
Signed-off-by: Ramakrishna Gottimukkula <rgottimu@codeaurora.org>