sm8450-common: display: Set debug.sf.auto_latch_unsignaled to 0

Need to explicitly set auto_latch_unsignaled property to
disabled state to keep latch-unsignaled as the default
behavior.

Change-Id: I3856caaf0a68e7e720819f25338d1eb9196f56b0

properties/vendor.prop

@@ -131,6 +131,7 @@ vendor.gatekeeper.disable_spu=true
 
 # Graphics
 debug.egl.hw=0
+debug.sf.auto_latch_unsignaled=0
 debug.sf.disable_client_composition_cache=1
 debug.sf.enable_gl_backpressure=1
 debug.sf.enable_hwc_vds=1