i915g: Remove 4444 and 5551 formats

They don't seem to work 100%, I need to investigate but in the
meantime let's remove them.

src/gallium/drivers/i915/TODO

@@ -34,5 +34,7 @@ Random list of problems with i915g:
 
 - Fix fragment discard
 
+- Fix 4444 and 5551 formats
+
 Other bugs can be found here:
 https://bugs.freedesktop.org/buglist.cgi?bug_status=NEW&bug_status=ASSIGNED&bug_status=REOPENED&component=Drivers/Gallium/i915g

src/gallium/drivers/i915/i915_screen.c

@@ -327,9 +327,7 @@ i915_is_format_supported(struct pipe_screen *screen,
       PIPE_FORMAT_B8G8R8X8_UNORM,
       PIPE_FORMAT_R8G8B8A8_UNORM,
       PIPE_FORMAT_R8G8B8X8_UNORM,
-      PIPE_FORMAT_B4G4R4A4_UNORM,
       PIPE_FORMAT_B5G6R5_UNORM,
-      PIPE_FORMAT_B5G5R5A1_UNORM,
       PIPE_FORMAT_B10G10R10A2_UNORM,
       PIPE_FORMAT_L8_UNORM,
       PIPE_FORMAT_A8_UNORM,
@@ -353,8 +351,6 @@ i915_is_format_supported(struct pipe_screen *screen,
       PIPE_FORMAT_R8G8B8A8_UNORM,
       PIPE_FORMAT_R8G8B8X8_UNORM,
       PIPE_FORMAT_B5G6R5_UNORM,
-      PIPE_FORMAT_B5G5R5A1_UNORM,
-      PIPE_FORMAT_B4G4R4A4_UNORM,
       PIPE_FORMAT_B10G10R10A2_UNORM,
       PIPE_FORMAT_L8_UNORM,
       PIPE_FORMAT_A8_UNORM,