MIPS: BCM47XX: Drop WGT634U hacks

This old wgt634u.c was trying to implement a bit ugly support for
Netgear WGT634U. It provided info about LED, flash mapping & layout and
was trying to handle reset button.

This is not needed anymore as we have replacement for all this stuff.

Signed-off-by: Rafał Miłecki <zajec5@gmail.com>
Signed-off-by: John Crispin <blogic@openwrt.org>
Patchwork: http://patchwork.linux-mips.org/patch/6302/