shader_enums: Move MAX_DRAW_BUFFERS to this file.

We include shader_enums.h from freedreno's compiler for both GL and
Vulkan, and the main/config.h include resulted in polluting the
namespace with things like MAX_VIEWPORTS that other Vulkan drivers use
as their driver-specific maximums.

Reviewed-by: Kristian H. Kristensen <hoegsberg@google.com>

src/compiler/shader_enums.h

@@ -27,7 +27,9 @@
 #define SHADER_ENUMS_H
 
 #include <stdbool.h>
-#include "mesa/main/config.h"
+
+/* Project-wide (GL and Vulkan) maximum. */
+#define MAX_DRAW_BUFFERS 8
 
 #ifdef __cplusplus
 extern "C" {

src/mesa/main/config.h

@@ -31,6 +31,7 @@
 #ifndef MESA_CONFIG_H_INCLUDED
 #define MESA_CONFIG_H_INCLUDED
 
+#include "compiler/shader_enums.h"
 
 /**
  * \name OpenGL implementation limits
@@ -224,12 +225,6 @@
 /*@}*/
 
 
-/** For GL_ARB_draw_buffers */
-/*@{*/
-#define MAX_DRAW_BUFFERS 8
-/*@}*/
-
-
 /** For GL_EXT_framebuffer_object */
 /*@{*/
 #define MAX_COLOR_ATTACHMENTS 8