wlan: Copy WCNSS_cfg.dat from respective path based on WLAN_PROPRIETARY

Copy WCNSS_cfg.dat file from firmware_bin of proprietary driver if the
flag WLAN_PROPRIETARY is set else copy from firmware_bin of opensource
wlan driver.

CRs-Fixed: 609383
Change-Id: I2f0a203537c000165cc2a27f2c1dfb678a085d6a
wlan: Release 3.2.3.244a

Revision 3.2.3.244a