Allow queryAngleChoice when ANGLE is system driver but is overridden

If ro.hardware.egl is set to "angle", but persist.graphics.egl is
set to a value that is not "angle", we should still allow egl loader to
load driver specified by persist.graphics.egl. Instead of skipping
queryAngleChoice() and always setup ANGLE when ro.hardware.egl is set to
"angle", we should proceed with queryAngleChoice(), and check what
ANGLE_GL_DRIVER_CHOICE_DEFAULT and ANGLE_GL_DRIVER_CHOICE_NATIVE
actually points to. If they still point to "angle", proceed with
setupAngleFromApk() || setupAngleFromSystem(). If they point to
"non-angle", early out and skip setupAngleFromAok() ||
setupAngleFromSystem().

Flag: android.os.query_angle_choice_flag
Test: make, flash and boot
Bug: b/408439360
Bug: b/409589250
Change-Id: I4f711aace7de1ef81ae4367dc5e3b5bfd946f97c