Avoid potential buffer over-read in shader, overrun in application.

indra/newview/app_settings/shaders/class1/avatar/objectSkinV.glsl

@@ -34,7 +34,7 @@ mat4 getObjectSkinnedTransform()
 	vec4 w = fract(weight4);
 	vec4 index = floor(weight4);
 	
-		 index = min(index, vec4(63.0));
+		 index = min(index, vec4(51.0));
 		 index = max(index, vec4( 0.0));
 
 	float scale = 1.0/(w.x+w.y+w.z+w.w);