[SCSI] zfcp: Cleanup of code in zfcp_scsi.c

Cleanup code in zfcp_scsi.c, fix coding style issues and simplify the
code.

Signed-off-by: Martin Petermann <martin@linux.vnet.ibm.com>
Signed-off-by: Christof Schmitt <christof.schmitt@de.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>