[Cleanup] Remove FindPatch() from struct_category.cpp and struct_category.h (#3130)

# Notes
- This is unused.

common/struct_strategy.cpp

@@ -71,14 +71,6 @@ namespace StructStrategyFactory {
 		strategies[first_opcode] = structs;
 	}
 
-	const StructStrategy *FindPatch(EmuOpcode first_opcode) {
-		std::map<EmuOpcode, const StructStrategy *>::const_iterator res;
-		res = strategies.find(first_opcode);
-		if(res == strategies.end())
-			return(nullptr);
-		return(res->second);
-	}
-
 };
 
 

common/struct_strategy.h

@@ -43,9 +43,6 @@ protected:
 //effectively a singleton, but I decided to do it this way for no apparent reason.
 namespace StructStrategyFactory {
 	void RegisterPatch(EmuOpcode first_opcode, const StructStrategy *structs);
-
-	//does NOT return ownership of the strategy.
-	const StructStrategy *FindPatch(EmuOpcode first_opcode);
 };