replace assert() calls with sfccheck() in SFCFile, because fuzzie is stupid
replace assert() calls with sfccheck() in SFCFile, because fuzzie is stupid

bdonlan/openc2e,ccdevnet/openc2e,bdonlan/openc2e,crystalline/openc2e,crystalline/openc2e,ccdevnet/openc2e,crystalline/openc2e,bdonlan/openc2e,bdonlan/openc2e,crystalline/openc2e,crystalline/openc2e,ccdevnet/openc2e,ccdevnet/openc2e,ccdevnet/openc2e,ccdevnet/openc2e