[SCSI] fusion - removing target_id/bus_id from the VirtDevice structure

It makes no sense in keeping the target_id and bus_id
in the VirtDevice structure, when it can be obtained
from the VirtTarget structure.

In addition, this patch fix's couple compilation bugs
in mptfc.c when MPT_DEBUG_FC is enabled. This
provided by Micheal Reed.

Signed-off-by: Eric Moore <Eric.Moore@lsil.com>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>