[][kernel][common][eth][Remove SGMII_FIXED_2G5 from Maxlinear PHY driver]

[Description]
Remove SGMII_FIXED_2G5 from Maxlinear PHY driver.

We no longer need SGMII_FIXED_2G5 after applying DEL_RXFIFO_CLR patch.

[Release-log]
N/A

Change-Id: I6d2aea74bcee679210867580394001221f609d21
Reviewed-on: https://gerrit.mediatek.inc/c/openwrt/feeds/mtk_openwrt_feeds/+/6538171
1 file changed