[][kernel][mt7988][eth][Add maximum power definition for SFP+]

[Description]
Add maximum power definition for SFP+.

If without this patch, SFP framework cannot enable high power mode
for high power modules.

[Release-log]
N/A


Change-Id: I89e6f1a813dad24dd727c85c2ac3feddefa7165a
Reviewed-on: https://gerrit.mediatek.inc/c/openwrt/feeds/mtk_openwrt_feeds/+/7020870
1 file changed