scsi: megaraid: Fix error check return value of register_chrdev()

stable inclusion
from stable-v5.10.121
commit 508add11af0954a10abc76974d47240b223fd3b6
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I5L6CQ

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=508add11af0954a10abc76974d47240b223fd3b6

--------------------------------

[ Upstream commit c5acd61d ]

If major equals 0, register_chrdev() returns an error code when it fails.
This function dynamically allocates a major and returns its number on
success, so we should use "< 0" to check it instead of "!".

Link: https://lore.kernel.org/r/20220418105755.2558828-1-lv.ruyi@zte.com.cnReported-by: NZeal Robot <zealci@zte.com.cn>
Signed-off-by: NLv Ruyi <lv.ruyi@zte.com.cn>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: NSasha Levin <sashal@kernel.org>
Signed-off-by: NZheng Zengkai <zhengzengkai@huawei.com>
Acked-by: NXie XiuQi <xiexiuqi@huawei.com>

drivers/scsi/megaraid.c

@@ -4634,7 +4634,7 @@ static int __init megaraid_init(void)
 	 * major number allocation.
 	 */
 	major = register_chrdev(0, "megadev_legacy", &megadev_fops);
-	if (!major) {
+	if (major < 0) {
 		printk(KERN_WARNING
 				"megaraid: failed to register char device\n");
 	}