filesystem: Fix CreateDirectory and DeleteFile

Add a check if dir is nullptr (does not exist)

Fixes save game creation in Hades

src/core/hle/service/filesystem/filesystem.cpp

@@ -79,7 +79,7 @@ ResultCode VfsDirectoryServiceWrapper::DeleteFile(const std::string& path_) cons
     }
 
     auto dir = GetDirectoryRelativeWrapped(backing, Common::FS::GetParentPath(path));
-    if (dir->GetFile(Common::FS::GetFilename(path)) == nullptr) {
+    if (dir == nullptr || dir->GetFile(Common::FS::GetFilename(path)) == nullptr) {
         return FileSys::ERROR_PATH_NOT_FOUND;
     }
     if (!dir->DeleteFile(Common::FS::GetFilename(path))) {
@@ -93,8 +93,9 @@ ResultCode VfsDirectoryServiceWrapper::DeleteFile(const std::string& path_) cons
 ResultCode VfsDirectoryServiceWrapper::CreateDirectory(const std::string& path_) const {
     std::string path(Common::FS::SanitizePath(path_));
     auto dir = GetDirectoryRelativeWrapped(backing, Common::FS::GetParentPath(path));
-    if (dir == nullptr && Common::FS::GetFilename(Common::FS::GetParentPath(path)).empty())
+    if (dir == nullptr || Common::FS::GetFilename(Common::FS::GetParentPath(path)).empty()) {
         dir = backing;
+    }
     auto new_dir = dir->CreateSubdirectory(Common::FS::GetFilename(path));
     if (new_dir == nullptr) {
         // TODO(DarkLordZach): Find a better error code for this