[][kernel][7988][eth][Adjust MDC/MDIO driving strength]

Change MDC/MDIO driving strength to 10mA.

Because the trace length of the EVB is longer than that of the RFB,
there may be potential signal integrity issues that can be resolved
by increasing driving strength.

If without this patch, the EVB may encounter a firmware loading
failure issue with the 10G PHY.


Change-Id: I2d6af280e6ab4ea64085569fd40580e52405121e
Reviewed-on: https://gerrit.mediatek.inc/c/openwrt/feeds/mtk_openwrt_feeds/+/7590203
14 files changed