How do I set the regulatory domain for my Sterling-LWB, -LWB5 and -LWB5+ module from release version 8.5.0.7 on?

There is three ways to set the regualtory domain from release version 8.5.0.7 on.

1. as a command line parameter when loading the brcmfmac.ko module. Example:
# insmod brcmfmac.ko regdomain="US"

2. in a config file in your root fs:
# cat /etc/modprobe.d/brcmfmac.conf
options brcmfmac regdomain=US

3. Device Tree setting
Device Tree setting is preferred. See Lairds Software Integration Guiide (SIG) on Github:
Sterling LWBx Series Radio Software Integration Guide