GPU: Fix errors handling texture remapping (#4745)

* GPU: Fix errors handling texture remapping

- Fixes an error where a pool entry and memory mapping changing at the same time could cause a texture to rebind its data from the wrong GPU VA (data swaps)
- Fixes an error where the texture pool could act on a mapping change before the mapping has actually been changed ("Unmapped" event happens before change, we need to signal it changed _after_ it completes)

TODO: remove textures from partially mapped list... if they aren't.

* Add Remap actions for handling post-mapping behaviours

* Remove unused code.

* Address feedback

* Nit

src/Ryujinx.Memory/Range/MultiRange.cs

@@ -319,5 +319,14 @@ namespace Ryujinx.Memory.Range
 
             return hash.ToHashCode();
         }
+
+        /// <summary>
+        /// Returns a string summary of the ranges contained in the MultiRange.
+        /// </summary>
+        /// <returns>A string summary of the ranges contained within</returns>
+        public override string ToString()
+        {
+            return HasSingleRange ? _singleRange.ToString() : string.Join(", ", _ranges);
+        }
     }
 }