Prior to commit 1496b95a ("x86: clean up default grub baudrate
settings") we had three different baud rates for the Geode targets:
19200 for net5501, 38400 for alix2, and 115200 for Geos.

It doesn't seem that there's a very good reason for varying from our
default 115200 baud, so let's make the Geode target do that instead.

Signed-off-by: David Woodhouse <dwmw2@infradead.org>