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 <rongqianfeng@vivo.com>
Link: https://lore.kernel.org/r/20250826093242.230344-1-rongqianfeng@vivo.com


Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>