swrast: remove MAX_WIDTH array in s_span.c

src/mesa/swrast/s_span.c

@@ -1319,7 +1319,8 @@ _swrast_write_rgba_span( struct gl_context *ctx, SWspan *span)
          /* color[fragOutput] will be written to buffer[buf] */
 
          if (rb) {
-            GLchan rgbaSave[MAX_WIDTH][4];
+            /* re-use one of the attribute array buffers for rgbaSave */
+            GLchan (*rgbaSave)[4] = (GLchan (*)[4]) span->array->attribs[0];
             struct swrast_renderbuffer *srb = swrast_renderbuffer(rb);
             GLenum colorType = srb->ColorType;