defconfig: 8974: Turn on disable of debug image for PS HOLD reset

set config item to build the watchdog debug controller for
enabling and disabling of debug image on MSM8974.
XPUs do not reset for non-watchdog resets when the watchdog debug
feature is enabled on MSM8974. Hence, for adb reboot to work, this
change is required.

Change-Id: Ied35a3f73fdfb5bb724b4611f5825af2481f6ffd
Signed-off-by: Pushkar Joshi <pushkarj@codeaurora.org>