Use vertex shader workaround for Mali GXX GPUs for glow shader

We applied this same workaround to the tonemap shader and DoF, but didn't apply it to glow since the bug didn't manifest on our test devices.

Author: clayjohn

servers/rendering/renderer_rd/shaders/effects/blur_raster.glsl

@@ -11,9 +11,22 @@ layout(location = 0) out vec2 uv_interp;
 /* clang-format on */
 
 void main() {
-	vec2 base_arr[3] = vec2[](vec2(-1.0, -1.0), vec2(-1.0, 3.0), vec2(3.0, -1.0));
-	gl_Position = vec4(base_arr[gl_VertexIndex], 0.0, 1.0);
-	uv_interp = clamp(gl_Position.xy, vec2(0.0, 0.0), vec2(1.0, 1.0)) * 2.0; // saturate(x) * 2.0
+	// old code, ARM driver bug on Mali-GXXx GPUs and Vulkan API 1.3.xxx
+	// https://github.com/godotengine/godot/pull/92817#issuecomment-2168625982
+	//vec2 base_arr[3] = vec2[](vec2(-1.0, -1.0), vec2(-1.0, 3.0), vec2(3.0, -1.0));
+	//gl_Position = vec4(base_arr[gl_VertexIndex], 0.0, 1.0);
+	//uv_interp = clamp(gl_Position.xy, vec2(0.0, 0.0), vec2(1.0, 1.0)) * 2.0; // saturate(x) * 2.0
+
+	vec2 vertex_base;
+	if (gl_VertexIndex == 0) {
+		vertex_base = vec2(-1.0, -1.0);
+	} else if (gl_VertexIndex == 1) {
+		vertex_base = vec2(-1.0, 3.0);
+	} else {
+		vertex_base = vec2(3.0, -1.0);
+	}
+	gl_Position = vec4(vertex_base, 0.0, 1.0);
+	uv_interp = clamp(vertex_base, vec2(0.0, 0.0), vec2(1.0, 1.0)) * 2.0; // saturate(x) * 2.0
 }
 
 /* clang-format off */