ppc: Zap Hymod board

Remove this board as this is the only one last user of eeprom_probe(),
which is pretty non-standard stuff.

This patch also removes all the PHP, SQL and CSS stuff from U-Boot,
which probably makes U-Boot a bit less IoT ;-)

Signed-off-by: Marek Vasut <marex@denx.de>
Cc: Masahiro Yamada <yamada.m@jp.panasonic.com>
Cc: Tom Rini <trini@ti.com>
Cc: Wolfgang Denk <wd@denx.de>
Cc: Simon Glass <sjg@chromium.org>
Cc: Heiko Schocher <hs@denx.de>