drm/radeon/kms: add LTE/GTE discard + rv515 two sided stencil register.

This adds some rv350+ register for LTE/GTE discard,
and enables the rv515 two sided stencil register.
It also disables the DEPTHXY_OFFSET register which
can be used to workaround the CS checker.
Moves rs690 to proper place in rs600 and uses correct
table on rs600.

Signed-off-by: Dave Airlie <airlied@redhat.com>
diff --git a/drivers/gpu/drm/radeon/r300.c b/drivers/gpu/drm/radeon/r300.c
index 053f4ec..051bca6 100644
--- a/drivers/gpu/drm/radeon/r300.c
+++ b/drivers/gpu/drm/radeon/r300.c
@@ -995,7 +995,7 @@
 	0x00000000, 0x00000000, 0x00000000, 0x00000000,
 	0x00000000, 0xFFFF0000, 0xFFFFFFFF, 0xFF80FFFF,
 	0x00000000, 0x00000000, 0x00000000, 0x00000000,
-	0x0003FC01, 0xFFFFFFF8, 0xFE800B19,
+	0x0003FC01, 0xFFFFFCF8, 0xFF800B19,
 };
 
 static int r300_packet0_check(struct radeon_cs_parser *p,