What is the correct way to set the country code for AP on orange pi 4?

I always received beacons with Country "US", until I created the file "brcmfmac43456-sdio.xunlong,orangepi-4.txt".
It is a copy of brcmfmac43456-sdio.txt and I added the line:

ccode=DE

With this modification, I see the expected beacon. (Country: "DE", correct tx-power, ...)
 

I think this is not the intended way to configure it.

What I checked before:

• My hostapd.conf contains;

...
country_code=DE
ieee80211d=1
...

• iw reg get 

global
country DE: DFS-ETSI
    (2400 - 2483 @ 40), (N/A, 20), (N/A)
    (5150 - 5250 @ 80), (N/A, 20), (N/A), NO-OUTDOOR, AUTO-BW
    (5250 - 5350 @ 80), (N/A, 20), (0 ms), NO-OUTDOOR, DFS, AUTO-BW
    (5470 - 5725 @ 160), (N/A, 26), (0 ms), DFS
    (5725 - 5875 @ 80), (N/A, 13), (N/A)
    (57000 - 66000 @ 2160), (N/A, 40), (N/A)

• Starting hostapd with "-d" prints "Beacon head" and "tail". I found "DE" in the hex-values but not "US".
• Tested configuration on Raspberri Pi ==> Beacon with expected country code "DE"

So all test returned the expected results but in the air I captured "US", wrong max power, ...

until I added the file "brcmfmac43456-sdio.xunlong,orangepi-4.txt" with the line "ccode=DE".