[SCSI] qla2xxx: fix msleep compile error

drivers/scsi/qla2xxx/qla_attr.c: In function 'qla24xx_vport_delete':
drivers/scsi/qla2xxx/qla_attr.c:1184: error: implicit declaration of function 'msleep'
make[3]: *** [drivers/scsi/qla2xxx/qla_attr.o] Error 1
make[3]: *** Waiting for unfinished jobs....

Reported-by: David Miller <davem@davemloft.net>
Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Acked-by: Andrew Vasquez <andrew.vasquez@qlogic.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>