scsi: megaraid_sas: Fix goto labels in error handling

During init, if pci_alloc_irq_vectors() fails, the driver has not yet setup
the IRQs. Fix the goto labels and error handling for this case.

Signed-off-by: Shivasharan S <shivasharan.srikanteshwara@broadcom.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>