vrend: Add support for VIRGL_FORMAT_R10G10B10A2_UINT

As Mesa doesn't support glReadPixel with GL_BGRA_INTEGER on GLES, add this
format so Virgl calls glReadPixel with GL_RGBA_INTEGER.

Fixes dEQP-GLES3.functional.fbo.color.clear.rgb10_a2ui

Signed-off-by: Tomeu Vizoso <tomeu.vizoso@collabora.com>
Tested-by: Jakob Bornecrantz <jakob@collabora.com>

src/virgl_hw.h

@@ -199,6 +199,8 @@ enum virgl_formats {
    VIRGL_FORMAT_R16G16B16X16_UNORM      = 234,
    VIRGL_FORMAT_R16G16B16X16_SNORM      = 235,
 
+   VIRGL_FORMAT_R10G10B10A2_UINT        = 253,
+
    VIRGL_FORMAT_BPTC_RGBA_UNORM         = 255,
    VIRGL_FORMAT_BPTC_SRGBA              = 256,
    VIRGL_FORMAT_BPTC_RGB_FLOAT          = 257,

src/vrend_formats.c

@@ -241,6 +241,7 @@ static struct vrend_format_table bit10_formats[] = {
   { VIRGL_FORMAT_B10G10R10A2_UINT, GL_RGB10_A2UI, GL_BGRA_INTEGER, GL_UNSIGNED_INT_2_10_10_10_REV, NO_SWIZZLE },
   { VIRGL_FORMAT_R10G10B10X2_UNORM, GL_RGB10_A2, GL_RGBA, GL_UNSIGNED_INT_2_10_10_10_REV, RGB1_SWIZZLE },
   { VIRGL_FORMAT_R10G10B10A2_UNORM, GL_RGB10_A2, GL_RGBA, GL_UNSIGNED_INT_2_10_10_10_REV, NO_SWIZZLE },
+  { VIRGL_FORMAT_R10G10B10A2_UINT, GL_RGB10_A2UI, GL_RGBA_INTEGER, GL_UNSIGNED_INT_2_10_10_10_REV, NO_SWIZZLE },
 };
 
 static struct vrend_format_table packed_float_formats[] = {