r600g: add fetch shader capabilities

Use fetch shader instead of having fetch instruction in the vertex
shader. Allow to restrict shader update to a smaller part when
vertex buffer input layout changes.

Signed-off-by: Jerome Glisse <jglisse@redhat.com>

src/gallium/drivers/r600/r600_shader.h

@@ -46,6 +46,7 @@ struct r600_shader {
 	struct r600_shader_io	output[32];
 	enum radeon_family	family;
 	boolean			uses_kill;
+	struct r600_bc		bc_fetch;
 };
 
 int r600_shader_from_tgsi(const struct tgsi_token *tokens, struct r600_shader *shader);