Realtek chips can program a specific country domain on efuse to
indicate what is the expected rtw_regulatory. For chips with a
programmed country domain, we set REGULATORY_STRICT_REG to tell
stack to consider follow-up regulatory_hint() as the superset of
our regulatory rule. Besides, on driver side, only the request via
NL80211_REGDOM_SET_BY_DRIVER, which matches programmed country
domain, will be handled to keep rtw_regulatory unchanged.

For worldwide roaming chips, i.e. ones without a specific programmed
country domain, system of distro can set expected regulatory via
NL80211_REGDOM_SET_BY_USER. With setting from it, rtw_regulatory
will handle the requests only via NL80211_REGDOM_SET_BY_USER to
follow setting from system of distro. REGULATORY_COUNTRY_IE_IGNORE
will then be set to tell stack to ignore country IE for us. The
restrictions mentioned above will remain until 00, i.e. worldwide,
is set via NL80211_REGDOM_SET_BY_USER.

On the other hand, for worldwide roamin chips, if there is no
specific regulatory set via NL80211_REGDOM_SET_BY_USER, requests
from all regulatory notifications will be handled by rtw_regulatory.
And REGULATORY_COUNTRY_IE_IGNORE won't be set.
Signed-off-by: Zong-Zhe Yang <kevin_yang@realtek.com>
Signed-off-by: Ping-Ke Shih <pkshih@realtek.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/20210830072014.12250-3-pkshih@realtek.com