filesystem: rename IVFileSystem009 to IFileSystem to avoid UBsan errors when debugging a mod that calls this interface using original headers

filesystem/VFileSystem009.cpp

@@ -81,7 +81,7 @@ static inline void CopyAndFixSlashes( char *p, const char *in, size_t size )
 	COM_FixSlashes( p );
 }
 
-class CXashFS : public IVFileSystem009
+class CXashFS : public IFileSystem
 {
 private:
 	class CSearchState

filesystem/VFileSystem009.h

@@ -40,7 +40,7 @@ public:
 	virtual ~IBaseInterface() {}
 };
 
-class IVFileSystem009 : public IBaseInterface {
+class IFileSystem : public IBaseInterface {
 public:
 	virtual void Mount() = 0; /* linkage=_ZN11IFileSystem5MountEv */