scsi: 3w-9xxx: Avoid disabling device if failing to enable it

The original code will "goto out_disable_device" and call
pci_disable_device() if pci_enable_device() fails. The kernel will generate
a warning message like "3w-9xxx 0000:00:05.0: disabling already-disabled
device".

We shouldn't disable a device that failed to be enabled. A simple return is
fine.

Link: https://lore.kernel.org/r/20220829110115.38789-1-fantasquex@gmail.com
Reported-by: Zheyu Ma <zheyuma97@gmail.com>
Signed-off-by: Letu Ren <fantasquex@gmail.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>