MT7612 calibration regression in 24.10.2

Device: NETGEAR R6220

In OpenWrt 24.10, Configured Antennas of the 5G phy become TX 0x202 RX 0x202 instead of TX 0x3 RX 0x3.

From this issue we can know this is a calibration problem: calibration data are being read from an incorrect offset.

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 OpenWrt 24.10.2, r28739-d9340319c6
 -----------------------------------------------------
root@OpenWrt:~# iw phy1 info
Wiphy phy1
        wiphy index: 1
        max # scan SSIDs: 4
        max scan IEs length: 2247 bytes
        max # sched scan SSIDs: 0
        max # match sets: 0
        Retry short limit: 7
        Retry long limit: 4
        Coverage class: 0 (up to 0m)
        Device supports AP-side u-APSD.
        Device supports T-DLS.
        Available Antennas: TX 0x3 RX 0x3
        Configured Antennas: TX 0x202 RX 0x202

 -----------------------------------------------------
 OpenWrt 23.05.5, r24106-10cc5fcd00
 -----------------------------------------------------
root@OpenWrt:~# iw phy1 info
Wiphy phy1
        wiphy index: 1
        max # scan SSIDs: 4
        max scan IEs length: 2247 bytes
        max # sched scan SSIDs: 0
        max # match sets: 0
        Retry short limit: 7
        Retry long limit: 4
        Coverage class: 0 (up to 0m)
        Device supports AP-side u-APSD.
        Device supports T-DLS.
        Available Antennas: TX 0x3 RX 0x3
        Configured Antennas: TX 0x3 RX 0x3

Start by reviewing the calibration-offset discussion in mt76 issue 980 and comparing MT7612 behavior between OpenWrt 24.10.2 and 23.05.5. Reproduce the issue with iw phy1 info on the NETGEAR R6220; done means the 5G phy reports Configured Antennas as TX 0x3 RX 0x3 rather than TX 0x202 RX 0x202.