vrend: use the correct gbm bgra formats

Now that the glTextureView() issues for eglimage-backed textures have
been discovered, we can switch back to using the right gbm formats for
externally allocated resources (this commit) and remove many of the
bgra-specific emulation (following commits).

Signed-off-by: Ryan Neph <ryanneph@google.com>
Reviewed-by: Gert Wollny <gert.wollny@collabora.com>
Part-of: <https://gitlab.freedesktop.org/virgl/virglrenderer/-/merge_requests/725>

src/vrend_winsys_gbm.c

@@ -99,8 +99,8 @@ static const struct planar_layout triplanar_yuv_420_layout = {
 
 static const struct format_conversion conversions[] = {
     { GBM_FORMAT_RGB565, VIRGL_FORMAT_B5G6R5_UNORM },
-    { GBM_FORMAT_ABGR8888, VIRGL_FORMAT_B8G8R8A8_UNORM },
-    { GBM_FORMAT_XBGR8888, VIRGL_FORMAT_B8G8R8X8_UNORM },
+    { GBM_FORMAT_ARGB8888, VIRGL_FORMAT_B8G8R8A8_UNORM },
+    { GBM_FORMAT_XRGB8888, VIRGL_FORMAT_B8G8R8X8_UNORM },
     { GBM_FORMAT_ABGR2101010, VIRGL_FORMAT_R10G10B10A2_UNORM },
     { GBM_FORMAT_ABGR16161616F, VIRGL_FORMAT_R16G16B16A16_FLOAT },
     { GBM_FORMAT_NV12, VIRGL_FORMAT_NV12 },