video_core: Add MMPX texture filter (#6564)

* video_core: Add MMPX texture shader

* mmpx: Apply mix to mask alpha edge artifacting

* mmpx: Do not use deprecated texture fuction.

src/common/settings.cpp

@@ -62,6 +62,8 @@ std::string_view GetTextureFilterName(TextureFilter filter) {
         return "ScaleForce";
     case TextureFilter::xBRZ:
         return "xBRZ";
+    case TextureFilter::MMPX:
+        return "MMPX";
     default:
         return "Invalid";
     }

src/common/settings.h

@@ -74,6 +74,7 @@ enum class TextureFilter : u32 {
     NearestNeighbor = 3,
     ScaleForce = 4,
     xBRZ = 5,
+    MMPX = 6
 };
 
 namespace NativeButton {