Derive operator!= from operator== (#1660)

src/gfx/pal_packing.cpp

@@ -87,7 +87,6 @@ private:
 		Iter() = default;
 
 		bool operator==(Iter const &rhs) const { return _iter == rhs._iter; }
-		bool operator!=(Iter const &rhs) const { return !operator==(rhs); }
 
 		Iter &operator++() {
 			++_iter;

src/gfx/process.cpp

@@ -466,7 +466,6 @@ public:
 			}
 
 			bool operator==(Iterator const &rhs) const { return coords() == rhs.coords(); }
-			bool operator!=(Iterator const &rhs) const { return !operator==(rhs); }
 		};
 
 	public: