coreboot_table: don't add CMOS checksum twice.

Checksum is already in cmos_layout.bin. No need to add it twice

Change-Id: I6d12f35fd8ff12eee9a17365bbfab38845c09574
Signed-off-by: Vladimir Serbinenko <phcoder@gmail.com>
Reviewed-on: http://review.coreboot.org/4829
Tested-by: build bot (Jenkins)
Reviewed-by: Alexandru Gagniuc <mr.nuke.me@gmail.com>
1 file changed