[GPU] Common resolve code based on compute shaders, swap MSAA samples 1 and 2, change ROV write rounding, random refactoring

src/xenia/gpu/d3d12/shaders/resolve_clear_32bpp.cs.hlsl

@@ -0,0 +1,26 @@
+#define XE_RESOLVE_CLEAR
+#include "resolve.hlsli"
+
+RWBuffer<uint4> xe_resolve_dest : register(u0);
+
+[numthreads(8, 8, 1)]
+void main(uint3 xe_thread_id : SV_DispatchThreadID) {
+  // 1 thread = 8 samples (same as resolve granularity).
+  uint2 extent_scale =
+      uint2(XeResolveEdramMsaaSamples() >= uint2(kXenosMsaaSamples_4X,
+                                                 kXenosMsaaSamples_2X));
+  // Group height is the same as resolve granularity, Y overflow check not
+  // needed.
+  [branch] if (xe_thread_id.x >= (XeResolveSizeDiv8().x << extent_scale.x)) {
+    return;
+  }
+  uint address_int4s =
+      XeEdramOffsetInts(
+          (xe_thread_id.xy << uint2(3u, 0u)) +
+              (XeResolveOffset() << extent_scale),
+          XeResolveEdramBaseTiles(), XeResolveEdramPitchTiles(),
+          kXenosMsaaSamples_1X, XeResolveEdramIsDepth(), 0u)
+      >> 2u;
+  xe_resolve_dest[address_int4s] = xe_resolve_clear_value.xxxx;
+  xe_resolve_dest[address_int4s + 1u] = xe_resolve_clear_value.xxxx;
+}