drivers: soc: xilinx: check return status of get_api_version()

Currently return status is not getting checked for get_api_version
and because of that for x86 arch we are getting below smatch error.

    CC      drivers/soc/xilinx/zynqmp_power.o
drivers/soc/xilinx/zynqmp_power.c: In function 'zynqmp_pm_probe':
drivers/soc/xilinx/zynqmp_power.c:295:12: warning: 'pm_api_version' is
used uninitialized [-Wuninitialized]
    295 |         if (pm_api_version < ZYNQMP_PM_VERSION)
        |            ^
    CHECK   drivers/soc/xilinx/zynqmp_power.c
drivers/soc/xilinx/zynqmp_power.c:295 zynqmp_pm_probe() error:
uninitialized symbol 'pm_api_version'.

So, check return status of pm_get_api_version and return error in case
of failure to avoid checking uninitialized pm_api_version variable.

Fixes: b9b3a8b ("firmware: xilinx: Remove eemi ops for get_api_version")
Signed-off-by: Jay Buddhabhatti <[email protected]>
Cc: [email protected]
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Michal Simek <[email protected]>

Author: jbuddhab

drivers/soc/xilinx/zynqmp_power.c

@@ -288,7 +288,9 @@ static int zynqmp_pm_probe(struct platform_device *pdev)
 	u32 pm_api_version, pm_family_code, pm_sub_family_code, node_id;
 	struct mbox_client *client;
 
-	zynqmp_pm_get_api_version(&pm_api_version);
+	ret = zynqmp_pm_get_api_version(&pm_api_version);
+	if (ret)
+		return ret;
 
 	/* Check PM API version number */
 	if (pm_api_version < ZYNQMP_PM_VERSION)