scsi: ibmvfc: Add Kconfig dependency on NVME_FC to prevent link failure

[pavrampu <pavrampu@linux.ibm.com>]

Hi,

I am seeing below build failure with latest linux-next repo.

Description:

Building the kernel with CONFIG_SCSI_IBMVFC=y and CONFIG_NVME_FC=m 
results in a link failure when building vmlinux:

Build failure logs:

ld: drivers/scsi/ibmvscsi/ibmvfc-nvme.o: in function 
`ibmvfc_nvme_register_remoteport':
ibmvfc-nvme.c:488: undefined reference to `nvme_fc_register_remoteport'
ld: drivers/scsi/ibmvscsi/ibmvfc-nvme.o: in function 
`ibmvfc_nvme_unregister_remoteport':
ibmvfc-nvme.c:515: undefined reference to 
`nvme_fc_unregister_remoteport'
ld: drivers/scsi/ibmvscsi/ibmvfc-nvme.o: in function 
`ibmvfc_nvme_register':
ibmvfc-nvme.c:536: undefined reference to `nvme_fc_register_localport'
ld: drivers/scsi/ibmvscsi/ibmvfc-nvme.o: in function 
`ibmvfc_nvme_unregister':
ibmvfc-nvme.c:565: undefined reference to `nvme_fc_unregister_localport'
ld: drivers/scsi/ibmvscsi/ibmvfc-nvme.o: in function 
`ibmvfc_nvme_unregister':
ibmvfc-nvme.c:565: undefined reference to `nvme_fc_unregister_localport'
ld: drivers/scsi/ibmvscsi/ibmvfc-core.c:6798: undefined reference to 
`nvme_fc_rescan_remoteport'

If you happen to fix this, please add below tag.

Reported-by: Pavithra <pavrampu@linux.ibm.com>

Thanks,
Pavithra