cfq-iosched: fix merge error

cfq-iosched: fix merge error

block/cfq-iosched.c: In function 'cfq_init_queue':
block/cfq-iosched.c:3690:14: error: 'cic_index_lock' undeclared (first use in this function)
block/cfq-iosched.c:3691:15: error: 'cic_index_ida' undeclared (first use in this function)
block/cfq-iosched.c:3691:34: error: 'struct cfq_data' has no member named 'cic_index'

Presumably this was not build tested with CONFIG_CFQ_GROUP_IOSCHED set.

Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Jens Axboe <axboe@kernel.dk>