docs: Add MESA_pack_invert and ANGLE_pack_reverse_row_order

Reviewed-by: Marek Olšák <marek.olsak@amd.com>
Reviewed-by: Eric Anholt <eric@anholt.net>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/3156>
diff --git a/docs/relnotes/new_features.txt b/docs/relnotes/new_features.txt
index e442ced..ea68c33 100644
--- a/docs/relnotes/new_features.txt
+++ b/docs/relnotes/new_features.txt
@@ -14,3 +14,5 @@
 driconf: add glx_extension_override
 driconf: add indirect_gl_extension_override
 VK_AMD_mixed_attachment_samples on RADV (GFX6-GFX7).
+GL_MESA_pack_invert on r100 and vieux
+GL_ANGLE_pack_reverse_row_order