Corrected cmd line for hostapd 

I had just figured out the problem with this, when it got reverted. So here is the working change for "Use pid even for hostapd rather then trying to guess with regex"
The problem was just the order of parameters on the hostapd command line:
usage: hostapd [-hdBKtv] [-P <PID file>] <configuration file(s)>
My WiFi comes up with proper authentication happening after this. /var/run has a pid file:
-rw-r--r--  1 root  wheel  6 Jan 30 14:09 /var/run/hostapd_ath0_wlan0.pid
And there is a hostapd process:
22633  ??  Ss     0:00.02 /usr/sbin/hostapd -B -P /var/run/hostapd_ath0_wlan0.pid /var/etc/hostapd_ath0_wlan0.conf
All seems well with the world:)