kernel: Add missing config option

Fixes: 4f683718 ("kernel: Update to version 4.4.194")
Signed-off-by: NHauke Mehrtens <hauke@hauke-m.de>

target/linux/generic/config-4.4

@@ -1754,6 +1754,7 @@ CONFIG_IP_ROUTE_VERBOSE=y
 # CONFIG_IR_STREAMZAP is not set
 # CONFIG_IR_TTUSBIR is not set
 # CONFIG_ISCSI_BOOT_SYSFS is not set
+# CONFIG_ISCSI_IBFT is not set
 # CONFIG_ISCSI_TCP is not set
 CONFIG_ISDN=y
 # CONFIG_ISDN_AUDIO is not set