ath11k: fix AP mode for QCA6390

For QCA6390, station vdev needs to delay startup but not for AP mode. On AP
mode vdev starts up immediately after bss peer is created in chanctx assignment
context.

This patch does not affect IPQ8074 family of devices.

Tested-on: QCA6390 hw2.0 PCI WLAN.HST.1.0.1-01740-QCAHSTSWPLZ_V2_TO_X86-1

Signed-off-by: Carl Huang <cjhuang@codeaurora.org>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/1601399736-3210-3-git-send-email-kvalo@codeaurora.org