Klocwork tool reported pointer 'rport' returned from call to function
fc_bsg_to_rport() may be NULL and will be dereferenced.

Add a fix to validate rport before dereferencing.

Cc: stable@vger.kernel.org
Signed-off-by: Shreyas Deodhar <sdeodhar@marvell.com>
Signed-off-by: Nilesh Javali <njavali@marvell.com>
Link: https://lore.kernel.org/r/20230607113843.37185-7-njavali@marvell.comReviewed-by: Himanshu Madhani <himanshu.madhani@oracle.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>