LibGL: Stub lots of map-related methods

This adds stubs for `glMap(1|2)(d|f)`, `glMapGrid(1|2)(d|f)`,
`glEvalCoord(1|2)(d|f)`, `glEvalMesh(1|2)` and `glEvalPoint(1|2)`.

Userland/Libraries/LibGL/CMakeLists.txt

@@ -6,6 +6,7 @@ set(SOURCES
     GLFog.cpp
     GLLights.cpp
     GLLists.cpp
+    GLMap.cpp
     GLMat.cpp
     GLStencil.cpp
     GLTexture.cpp