mesa: add OES_sample_variables to extension table, add enable bit

Signed-off-by: Ilia Mirkin <imirkin@alum.mit.edu>
Reviewed-by: Dave Airlie <airlied@redhat.com>
Reviewed-by: Ian Romanick <ian.d.romanick@intel.com>

src/mesa/main/extensions_table.h

@@ -330,6 +330,7 @@ EXT(OES_point_sprite                        , ARB_point_sprite
 EXT(OES_query_matrix                        , dummy_true                             ,  x ,  x , ES1,  x , 2003)
 EXT(OES_read_format                         , dummy_true                             , GLL, GLC, ES1,  x , 2003)
 EXT(OES_rgb8_rgba8                          , dummy_true                             ,  x ,  x , ES1, ES2, 2005)
+EXT(OES_sample_variables                    , OES_sample_variables                   ,  x ,  x ,  x ,  30, 2014)
 EXT(OES_shader_image_atomic                 , ARB_shader_image_load_store            ,  x ,  x ,  x ,  31, 2015)
 EXT(OES_single_precision                    , dummy_true                             ,  x ,  x , ES1,  x , 2003)
 EXT(OES_standard_derivatives                , OES_standard_derivatives               ,  x ,  x ,  x , ES2, 2005)

src/mesa/main/mtypes.h

@@ -3911,6 +3911,7 @@ struct gl_extensions
    GLboolean EXT_transform_feedback;
    GLboolean EXT_timer_query;
    GLboolean EXT_vertex_array_bgra;
+   GLboolean OES_sample_variables;
    GLboolean OES_standard_derivatives;
    GLboolean OES_texture_buffer;
    /* vendor extensions */