net: mscc: ocelot: don't rely on cached verify_status in ocelot_port_get_mm()

ocelot_mm_update_port_status() updates mm->verify_status, but when the
verification state of a port changes, an IRQ isn't emitted, but rather,
only when the verification state reaches one of the final states (like
DISABLED, FAILED, SUCCEEDED) - things that would affect mm->tx_active,
which is what the IRQ *is* actually emitted for.

That is to say, user space may miss reports of an intermediary MAC Merge
verification state (like from INITIAL to VERIFYING), unless there was an
IRQ notifying the driver of the change in mm->tx_active as well.

This is not a huge deal, but for reliable reporting to user space, let's
call ocelot_mm_update_port_status() synchronously from
ocelot_port_get_mm(), which makes user space see the current MM status.
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

drivers/net/ethernet/mscc/ocelot_mm.c

@@ -205,6 +205,7 @@ int ocelot_port_get_mm(struct ocelot *ocelot, int port,
 	state->tx_min_frag_size = ethtool_mm_frag_size_add_to_min(add_frag_size);
 	state->rx_min_frag_size = ETH_ZLEN;
 
+	ocelot_mm_update_port_status(ocelot, port);
 	state->verify_status = mm->verify_status;
 	state->tx_active = mm->tx_active;