skd: fix msix error handling

As reported by gcc -Wmaybe-uninitialized, the cleanup path for
skd_acquire_msix tries to free the already allocated msi-x vectors
in reverse order, but the index variable may not have been
used yet:

drivers/block/skd_main.c: In function ‘skd_acquire_irq’:
drivers/block/skd_main.c:3890:8: error: ‘i’ may be used uninitialized in this function [-Werror=maybe-uninitialized]

This changes the failure path to skip releasing the interrupts
if we have not started requesting them yet.

Fixes: 180b0ae77d49 ("skd: use pci_alloc_irq_vectors")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>

drivers/block/skd_main.c

@@ -3849,7 +3849,7 @@ static int skd_acquire_msix(struct skd_device *skdev)
 	if (rc < 0) {
 		pr_err("(%s): failed to enable MSI-X %d\n",
 		       skd_name(skdev), rc);
-		goto msix_out;
+		goto out;
 	}
 
 	skdev->msix_entries = kcalloc(SKD_MAX_MSIX_COUNT,
@@ -3858,7 +3858,7 @@ static int skd_acquire_msix(struct skd_device *skdev)
 		rc = -ENOMEM;
 		pr_err("(%s): msix table allocation error\n",
 		       skd_name(skdev));
-		goto msix_out;
+		goto out;
 	}
 
 	/* Enable MSI-X vectors for the base queue */
@@ -3889,6 +3889,7 @@ static int skd_acquire_msix(struct skd_device *skdev)
 msix_out:
 	while (--i >= 0)
 		devm_free_irq(&pdev->dev, pci_irq_vector(pdev, i), skdev);
+out:
 	kfree(skdev->msix_entries);
 	skdev->msix_entries = NULL;
 	return rc;