scsi: mvumi: Use true and false for bool variable

Fix the following coccicheck warnings:

./drivers/scsi/mvumi.c:69:9-10: WARNING: return of 0/1 in function
'tag_is_empty' with return type bool.

Link: https://lore.kernel.org/r/[e-mail]
Reported-by: Abaci Robot <[e-mail]>
Signed-off-by: Jiapeng Chong <[e-mail]>
Signed-off-by: Martin K. Petersen <[e-mail]>

drivers/scsi/mvumi.c

···
 static bool tag_is_empty(struct mvumi_tag *st)
 {
 	if (st->top == 0)
-		return 1;
+		return true;
 	else
-		return 0;
+		return false;
 }
 
 static void mvumi_unmap_pci_addr(struct pci_dev *dev, void **addr_array)