stratosphere: use SdkMutex/SdkRecursiveMutex over Mutex

stratosphere/ams_mitm/source/fs_mitm/fsmitm_romfs.cpp

@@ -258,8 +258,8 @@ namespace ams::mitm::fs {
                 }
             }
 
-            os::Mutex g_fs_romfs_path_lock(false);
-            char g_fs_romfs_path_buffer[fs::EntryNameLengthMax + 1];
+            constinit os::SdkMutex g_fs_romfs_path_lock;
+            constinit char g_fs_romfs_path_buffer[fs::EntryNameLengthMax + 1];
 
             NOINLINE void OpenFileSystemRomfsDirectory(FsDir *out, ncm::ProgramId program_id, BuildDirectoryContext *parent, fs::OpenDirectoryMode mode, FsFileSystem *fs) {
                 std::scoped_lock lk(g_fs_romfs_path_lock);