watchdog: rti-wdt: Fix pm_runtime_get_sync() error checking

stable inclusion
from stable-v5.10.122
commit b3354f2046ccae8a8c941511dfc22f03a859500c
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I5W6OE

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=b3354f2046ccae8a8c941511dfc22f03a859500c

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

[ Upstream commit b3ac0c58 ]

If the device is already in a runtime PM enabled state
pm_runtime_get_sync() will return 1, so a test for negative
value should be used to check for errors.

Fixes: 2d63908b ("watchdog: Add K3 RTI watchdog support")
Signed-off-by: NMiaoqian Lin <linmq006@gmail.com>
Reviewed-by: NGuenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/20220412070824.23708-1-linmq006@gmail.comSigned-off-by: NGuenter Roeck <linux@roeck-us.net>
Signed-off-by: NWim Van Sebroeck <wim@linux-watchdog.org>
Signed-off-by: NSasha Levin <sashal@kernel.org>
Signed-off-by: NZheng Zengkai <zhengzengkai@huawei.com>
Reviewed-by: NWei Li <liwei391@huawei.com>

drivers/watchdog/rti_wdt.c

@@ -227,7 +227,7 @@ static int rti_wdt_probe(struct platform_device *pdev)
 
 	pm_runtime_enable(dev);
 	ret = pm_runtime_get_sync(dev);
-	if (ret) {
+	if (ret < 0) {
 		pm_runtime_put_noidle(dev);
 		pm_runtime_disable(&pdev->dev);
 		return dev_err_probe(dev, ret, "runtime pm failed\n");