- fixed compilation on POSIX-like platforms

src/p_udmf.cpp:2052:6: error: no matching member function for call to 'OpenMem'
src/sc_man.h:24:7: note: candidate function not viable: expects an l-value for 2nd argument
src/sc_man.h:23:7: note: candidate function not viable: requires 3 arguments, but 2 were provided
src/resourcefiles/file_directory.cpp:198:32: error: use of undeclared identifier 'Filename'; did you mean 'FileName'?

src/resourcefiles/file_directory.cpp

@@ -195,7 +195,7 @@ int FDirectory::AddDirectory(const char *dirpath)
 		return 0;
 	}
 
-	const size_t namepos = strlen(Filename);
+	const size_t namepos = strlen(FileName);
 	FString pathfix;
 
 	while ((ent = fts_read(fts)) != NULL)

src/sc_man.h

@@ -21,7 +21,7 @@ public:
 	void Open(const char *lumpname);
 	bool OpenFile(const char *filename);
 	void OpenMem(const char *name, const char *buffer, int size);
-	void OpenMem(const char *name, TArray<uint8_t> &buffer)
+	void OpenMem(const char *name, const TArray<uint8_t> &buffer)
 	{
 		OpenMem(name, (const char*)buffer.Data(), buffer.Size());
 	}