defconfig: 8660: Enable TZ log device

msm_devcie_tz_log is a debugfs module that displays
the contents of a buffer located in IMEM.  The contents
of this hold diagnostic information logged in by modules
running on secure domain.
This patch enables this tz_log debugfs module for 8x60
target device by setting CONFIG_MSM_TZ_LOG

Change-Id: Ic9ed0a4fc0596534728da14a045044d5d3fabf15
Signed-off-by: Mona Hossain <mhossain@codeaurora.org>