scsi: pm8001: Use int instead of u32 to store error codes

Use int instead of u32 for 'ret' variable to store negative error codes
returned by PM8001_CHIP_DISP->set_nvmd_req().

Signed-off-by: Qianfeng Rong <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Martin K. Petersen <[e-mail]>

drivers/scsi/pm8001/pm8001_ctl.c

···
 	struct pm8001_ioctl_payload	*payload;
 	DECLARE_COMPLETION_ONSTACK(completion);
 	u8		*ioctlbuffer;
-	u32		ret;
+	int		ret;
 	u32		length = 1024 * 5 + sizeof(*payload) - 1;
 
 	if (pm8001_ha->fw_image->size > 4096) {