Fix access denials for libEGL props

vendor.debug.egl.changepixelformat and vendor.debug.prerotation.disable
are used by libEGL (one of same-process HALs).
So they should be public-readable because libEGL can be loaded from
almost everywhere.

Bug: 80135368
Test: succeeded building and tested with taimen
Change-Id: I2e9c0809a4868329ab76a94800a144283f523579
diff --git a/sepolicy/vendor/property_contexts b/sepolicy/vendor/property_contexts
index a10b676..80239a4 100644
--- a/sepolicy/vendor/property_contexts
+++ b/sepolicy/vendor/property_contexts
@@ -46,6 +46,8 @@
 ro.boot.hardware.ddr       u:object_r:public_vendor_default_prop:s0
 ro.boot.hardware.ufs       u:object_r:public_vendor_default_prop:s0
 ro.qcom.adreno.            u:object_r:public_vendor_default_prop:s0
+vendor.debug.egl.changepixelformat  u:object_r:public_vendor_default_prop:s0
+vendor.debug.prerotation.disable  u:object_r:public_vendor_default_prop:s0
 
 # public_vendor_system_prop
 # They are public_vendor_system_props for vendor-specific extension.