[][kernel][common][eth][Fix warning of return with a value in returning void function]

[Description]
Fix warning of return with a value in returning void function.

[Release-log]
N/A


Change-Id: I047346ee8ab3984d5df9f583be887ea03357efee
Reviewed-on: https://gerrit.mediatek.inc/c/openwrt/feeds/mtk_openwrt_feeds/+/9227257
1 file changed