As most platforms implement the PROM serial interface prom_putchar()
add a simple bridge to allow re-using this code for zboot.
Signed-off-by: NAlban Bedel <albeu@free.fr>
Cc: Alex Smith <alex.smith@imgtec.com>
Cc: Andrew Bresticker <abrestic@chromium.org>
Cc: Wu Zhangjin <wuzhangjin@gmail.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/11811/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>