amd/geode_lx: Remove most boards

There is active work to convert remaining two boards,
PC Engines alix1c and alix2d, to EARLY_CBMEM_INIT.

Change-Id: I87e3963af7ef719e9fa2a8b0df34a896265905f0
Signed-off-by: Kyösti Mälkki <kyosti.malkki@gmail.com>
Reviewed-on: https://review.coreboot.org/26824
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
124 files changed