Use GLSL version 110 for OpenGL 2 shaders.

According to docs and Intel legacy drivers,
GLSL version 130 is for GL 3.0 not GL 2.0/2.1

Validated files with reference compiler from
https://www.khronos.org/opengles/sdk/tools/Reference-Compiler/

gdk/resources/glsl/gl2-texture-2d.fs.glsl

@@ -1,4 +1,4 @@
-#version 130
+#version 110
 
 varying vec2 vUv;
 

gdk/resources/glsl/gl2-texture-2d.vs.glsl

@@ -1,6 +1,4 @@
-#version 130
-
-uniform sampler2D map;
+#version 110
 
 attribute vec2 position;
 attribute vec2 uv;

gdk/resources/glsl/gl2-texture-rect.fs.glsl

@@ -1,4 +1,4 @@
-#version 130
+#version 110
 
 varying vec2 vUv;
 

gdk/resources/glsl/gl2-texture-rect.vs.glsl

@@ -1,6 +1,4 @@
-#version 130
-
-uniform sampler2DRect map;
+#version 110
 
 attribute vec2 position;
 attribute vec2 uv;

gdk/resources/glsl/gl3-texture-2d.vs.glsl

@@ -1,7 +1,5 @@
 #version 150
 
-uniform sampler2D map;
-
 in vec2 position;
 in vec2 uv;
 

gdk/resources/glsl/gl3-texture-rect.vs.glsl

@@ -1,7 +1,5 @@
 #version 150
 
-uniform sampler2DRect map;
-
 attribute vec2 position;
 attribute vec2 uv;