net: stmmac: dwmac-nuvoton: fix NULL pointer dereference in nvt_set_phy_intf_sel()

net: stmmac: dwmac-nuvoton: fix NULL pointer dereference in nvt_set_phy_intf_sel()

priv->dev was never initialized after devm_kzalloc() allocates the
private data structure. When nvt_set_phy_intf_sel() is later invoked
via the phylink interface_select callback, it calls
nvt_gmac_get_delay(priv->dev, ...) which dereferences the NULL pointer.

Fix this by assigning priv->dev = dev immediately after allocation.

Fixes: 4d7c557f58ef ("net: stmmac: dwmac-nuvoton: Add dwmac glue for Nuvoton MA35 family")
Signed-off-by: Joey Lu <a0987203069@gmail.com>
Link: https://patch.msgid.link/20260506084614.192894-2-a0987203069@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>