Fix Intel GPU initialization context (#2161)

This will fix some weird green lines appearing only on Intel GPUs, while using OpenGL.

src/glcontext_wgl.cpp

@@ -170,15 +170,17 @@ namespace bgfx { namespace gl
 			{
 				int32_t attrs[] =
 				{
-					WGL_SAMPLE_BUFFERS_ARB, 0,
-					WGL_SAMPLES_ARB, 0,
-					WGL_SUPPORT_OPENGL_ARB, true,
+					WGL_DRAW_TO_WINDOW_ARB, GL_TRUE,
+					WGL_SUPPORT_OPENGL_ARB, GL_TRUE,
+					WGL_DOUBLE_BUFFER_ARB, GL_TRUE,
 					WGL_PIXEL_TYPE_ARB, WGL_TYPE_RGBA_ARB,
-					WGL_DRAW_TO_WINDOW_ARB, true,
-					WGL_DOUBLE_BUFFER_ARB, true,
+					WGL_ACCELERATION_ARB, WGL_FULL_ACCELERATION_ARB,
 					WGL_COLOR_BITS_ARB, 32,
+					WGL_ALPHA_BITS_ARB, 8,
 					WGL_DEPTH_BITS_ARB, 24,
 					WGL_STENCIL_BITS_ARB, 8,
+					WGL_SAMPLE_BUFFERS_ARB, GL_TRUE,
+					WGL_SAMPLES_ARB, 4,
 					0
 				};