[Base] Fix infinite recursion on Posix filesystem

When listing all files in a folder, ignore hidden files (which start
with a dot). This prevents parsing ".." as a folder to enter, thus going
back one level and entering an infinite loop of folders to parse.

src/xenia/base/filesystem_posix.cc

@@ -219,6 +219,10 @@ std::vector<FileInfo> ListFiles(const std::filesystem::path& path) {
   while (auto ent = readdir(dir)) {
     FileInfo info;
 
+    if (ent->d_name[0] == '.') {
+      continue;
+    }
+
     info.name = ent->d_name;
     struct stat st;
     stat((path / info.name).c_str(), &st);