cpu: microblaze: add error handling in microblaze_cpu_get_desc()

Check snprintf() return value for errors.

Make microblaze_cpu_get_desc() directly return snprintf() error code if
ret < 0. Otherwise, if the return value is greater than or equal to size,
the resulting string is truncated, so return -ENOSPC.

Fixes: 816226d27e ("cpu: add CPU driver for microblaze")
Signed-off-by: Ovidiu Panait <ovpanait@gmail.com>
Link: https://lore.kernel.org/r/20220829170205.1274484-2-ovpanait@gmail.com
Signed-off-by: Michal Simek <michal.simek@amd.com>
diff --git a/drivers/cpu/microblaze_cpu.c b/drivers/cpu/microblaze_cpu.c
index 969a104..b9d0792 100644
--- a/drivers/cpu/microblaze_cpu.c
+++ b/drivers/cpu/microblaze_cpu.c
@@ -97,8 +97,10 @@
 	ret = snprintf(buf, size,
 		       "MicroBlaze @ %uMHz, Rev: %s, FPGA family: %s",
 		       cpu_freq_mhz, cpu_ver, fpga_family);
+	if (ret < 0)
+		return ret;
 
-	return 0;
+	return (ret >= size) ? -ENOSPC : 0;
 }
 
 static int microblaze_cpu_get_info(const struct udevice *dev,