Add restrict qualifier for images.

reference/shaders/comp/coherent-image.comp

@@ -6,7 +6,7 @@ layout(binding = 1, std430) coherent restrict writeonly buffer SSBO
     ivec4 value;
 } _10;
 
-layout(binding = 3, r32i) uniform coherent readonly mediump iimage2D uImage;
+layout(binding = 3, r32i) uniform coherent restrict readonly mediump iimage2D uImage;
 
 void main()
 {

spirv_glsl.cpp

@@ -6079,6 +6079,8 @@ string CompilerGLSL::to_qualifiers_glsl(uint32_t id)
 	{
 		if (flags & (1ull << DecorationCoherent))
 			res += "coherent ";
+		if (flags & (1ull << DecorationRestrict))
+			res += "restrict ";
 		if (flags & (1ull << DecorationNonWritable))
 			res += "readonly ";
 		if (flags & (1ull << DecorationNonReadable))