mt76x0: init: use mt76x02_mac_wcid_setup for wcid configuration

Use mt76x02_mac_wcid_setup utility routine for wcid init configuration
and remove duplicated code. This patch fixes a mt76x0 AP issue since
hw key table selection was set to pairwise by default

Fixes: dbad2adcb2c7 ("mt76x0: pci: enable AP support")
Signed-off-by: Lorenzo Bianconi <lorenzo.bianconi@redhat.com>
Signed-off-by: Felix Fietkau <nbd@nbd.name>