MIPS: ralink: cleanup early_printk

Add support for the new MT7621/8 SoC and kill ifdefs.
Cleanup some whitespace error while we are at it.

Signed-off-by: John Crispin <blogic@openwrt.org>
Patchwork: http://patchwork.linux-mips.org/patch/8028/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>