Add support for ARB_texture_multisample

GLSL Version : >= 140

Purpose:
Allow users to use features by enabling this extension, even in low versions.

Extension Name:
ARB_texture_multisample

Builtin-variables:
Nah

Builtin-functions:
Nah

Keywords:
      sampler2DMS, isampler2DMS, usampler2DMS,
      sampler2DMSArray, isampler2DMSArray, usampler2DMSArray

Reference:
https://www.khronos.org/registry/OpenGL/extensions/ARB/ARB_texture_multisample.txt

Test/140.frag

@@ -17,6 +17,7 @@ void main()
 #error GL_ES is not set
 #endif
 
+
 in struct S { float f; } s; // ERROR
 
 float patch = 3.1;
@@ -51,3 +52,9 @@ float fooi()
 {
     return i1 + i2;
 }
+
+uniform sampler2DMS aaa1; // ERROR
+
+#extension GL_ARB_texture_multisample : enable
+
+uniform sampler2DMS aaa2;