net: dsa: realtek: Fix LED group port bit for non-zero LED group

net: dsa: realtek: Fix LED group port bit for non-zero LED group

The rtl8366rb_led_group_port_mask() function always returns LED port
bit in LED group 0; the switch statement returns the same thing in all
non-default cases.

This means that the driver does not currently support configuring LEDs
in non-zero LED groups.

Fix this.

Fixes: 32d617005475a71e ("net: dsa: realtek: add LED drivers for rtl8366rb")
Signed-off-by: Marek Behún <kabel@kernel.org>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Link: https://patch.msgid.link/20260311111237.29002-1-kabel@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>