net: dsa: mt7530: populate lpi_interfaces to fix EEE support

phylink_create() decides once and for all that a MAC supports managed
EEE, and it requires the tx_lpi ops plus non-empty lpi_capabilities and
lpi_interfaces. mt753x_phylink_get_caps() leaves lpi_interfaces empty.

So ever since the conversion to phylink managed EEE, ethtool has
answered "Not supported" on every mt753x port, and phy_disable_eee()
has locked userspace out of turning EEE on. That undoes what
commit 06dfcd4098cf ("net: dsa: mt7530: fix enabling EEE on MT7531
switch on all boards") arranged: EEE off by default, but reachable
with ethtool.

Leave the speeds above 1 Gbps out of both bitmaps. PMCR folds
SPEED_2500 and SPEED_10000 onto PMCR_FORCE_SPEED_1000, so
PMCR_FORCE_EEE1G would govern LPI on such a link, and that is
unvalidated rather than known unsupported: MediaTek's SDK driver sets
the EEE force bits for 100 Mbps and 1 Gbps only, and the unit of the
wakeup timers is undocumented with the port clock at 2.5 times the
rate.

LPI stays off until userspace enables it, but the EEE advertisement of
a PHY that advertises it out of reset comes back, since phylink stops
force-clearing it.

Fixes: 9cf21773f535 ("net: dsa: mt7530: convert to phylink managed EEE")
Signed-off-by: Aleksei Sviridkin <f@lex.la>
Link: https://patch.msgid.link/20260903123644.23800-2-f@lex.la
Signed-off-by: Paolo Abeni <pabeni@redhat.com>