kern/efi: Fix memory leak on failure

Free the memory allocated to name before returning on failure.

Fixes: CID 296222

Signed-off-by: Darren Kenny <darren.kenny@oracle.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>

grub-core/kern/efi/efi.c

@@ -410,6 +410,7 @@ grub_efi_get_filename (grub_efi_device_path_t *dp0)
 	    {
 	      grub_error (GRUB_ERR_OUT_OF_RANGE,
 			  "malformed EFI Device Path node has length=%d", len);
+	      grub_free (name);
 	      return NULL;
 	    }