maxwell_3d: Fix depth clamping register

Using deko3d as reference:
4e47ba0013/source/maxwell/gpu_3d_state.cpp (L42)

We were using bits 3 and 4 to determine depth clamping, but these are
the same both enabled and disabled:

state->depthClampEnable ? 0x101A : 0x181D

The same happens on Nvidia's OpenGL driver, where they do something like
this (default capabilities, GL 4.5 compatibility):

(state & DEPTH_CLAMP) != 0 ? 0x201a : 0x281c

There's always a difference between the first bits in this register, but
bit 11 is consistently disabled on both deko3d/NVN and OpenGL. This
commit changes yuzu's behaviour to use bit 11 to determine depth
clamping.

- Fixes depth issues on Super Mario Odyssey's intro.

src/video_core/renderer_opengl/gl_rasterizer.cpp

@@ -999,11 +999,7 @@ void RasterizerOpenGL::SyncDepthClamp() {
     }
     flags[Dirty::DepthClampEnabled] = false;
 
-    const auto& state = gpu.regs.view_volume_clip_control;
-    UNIMPLEMENTED_IF_MSG(state.depth_clamp_far != state.depth_clamp_near,
-                         "Unimplemented depth clamp separation!");
-
-    oglEnable(GL_DEPTH_CLAMP, state.depth_clamp_far || state.depth_clamp_near);
+    oglEnable(GL_DEPTH_CLAMP, gpu.regs.view_volume_clip_control.depth_clamp_disabled == 0);
 }
 
 void RasterizerOpenGL::SyncClipEnabled(u32 clip_mask) {