ARM: amba: Fix wrong indentation in driver_override_store()

Indentation is one TAB and 7 spaces instead of 2 TABs.

Fixes: 3cf38571 ("ARM: 8256/1: driver coamba: add device binding path 'driver_override'")
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Todd Kjos <tkjos@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>