mesa: Update _mesa_has_geometry_shaders

Updates the _mesa_has_geometry_shaders function to also look
for OpenGL ES 3.1 contexts that has OES_geometry_shader enabled.
Reviewed-by: Matt Turner <mattst88@gmail.com>
Reviewed-by: Ilia Mirkin <imirkin@alum.mit.edu>
Reviewed-by: Ian Romanick <ian.d.romanick@intel.com>

src/mesa/main/context.h

@@ -330,7 +330,8 @@ _mesa_is_gles31(const struct gl_context *ctx)
 static inline bool
 _mesa_has_geometry_shaders(const struct gl_context *ctx)
 {
-   return _mesa_is_desktop_gl(ctx) && ctx->Version >= 32;
+   return _mesa_has_OES_geometry_shader(ctx) ||
+          (_mesa_is_desktop_gl(ctx) && ctx->Version >= 32);
 }