astbmc/common: add FWTS annotation
astbmc/common: add FWTS annotation

Just one annotation here, pretty rare situation I think... but
best to bail on this one, as this certainly isn't something we
want in production.

Signed-off-by: Stewart Smith <ec31ab75ddf977353c8f660f92ea8b23f64aef25@linux.vnet.ibm.com>

stewart-ibm/skiboot,qemu/skiboot,shenki/skiboot,shenki/skiboot,qemu/skiboot,legoater/skiboot,qemu/skiboot,shenki/skiboot,mikey/skiboot,legoater/skiboot,stewart-ibm/skiboot,shenki/skiboot,legoater/skiboot,qemu/skiboot,legoater/skiboot,open-power/skiboot,open-power/skiboot,mikey/skiboot,open-power/skiboot,open-power/skiboot,stewart-ibm/skiboot,shenki/skiboot,open-power/skiboot,legoater/skiboot,mikey/skiboot,qemu/skiboot