make runtime compatible with wasm

runtime/internal/lib/os/removeall_at.go

@@ -209,14 +209,3 @@ func openDirAt(dirfd int, name string) (*File, error) {
 	// We use kindNoPoll because we know that this is a directory.
 	return newFile(r, name, kindNoPoll), nil
 }
-
-// endsWithDot reports whether the final component of path is ".".
-func endsWithDot(path string) bool {
-	if path == "." {
-		return true
-	}
-	if len(path) >= 2 && path[len(path)-1] == '.' && IsPathSeparator(path[len(path)-2]) {
-		return true
-	}
-	return false
-}