qcacmn: Add a configure interface to get max_peers from OL_IF to DP

Currently max_peer value is hardcoded with DP wlan_cfg. This change adds
a generic interface to obtain a configuration parameter from OL_IF and
store in DP

Change-Id: Id437ab3bcd02fb1cbcbe8b56d55d19780af87066
CRs-Fixed: 2004658
6 files changed