There's a merged pull request on the void-packages repository

rpi-firmware: add firmware for zero 2w
https://github.com/void-linux/void-packages/pull/39123

Description:
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This took some figuring out, there's no documentation anywhere except a couple commit messages and blog posts.

- https://picockpit.com/raspberry-pi/raspberry-pi-zero-2-w-wifi-chipset-speeds-monitor-mode/
- https://github.com/RPi-Distro/firmware-nonfree/issues/24
- https://github.com/RPi-Distro/firmware-nonfree/commit/bda9207acee945633464e89614f3717b856579b5

#### Testing the changes
- I tested the changes in this PR: **YES**
```
# dmesg -H | grep brcmfmac
[  +0.105226] brcmfmac: brcmf_fw_alloc_request: using brcm/brcmfmac43436-sdio for chip BCM43430/2
[  +0.001051] usbcore: registered new interface driver brcmfmac
[  +0.003262] brcmfmac mmc1:0001:1: Direct firmware load for brcm/brcmfmac43436-sdio.raspberrypi,model-zero-2-w.bin failed with error -2
[  +0.030631] brcmfmac: brcmf_fw_alloc_request: using brcm/brcmfmac43436-sdio for chip BCM43430/2
[  +0.005169] brcmfmac: brcmf_fw_alloc_request: using brcm/brcmfmac43436-sdio for chip BCM43430/2
[  +0.025214] brcmfmac: brcmf_c_preinit_dcmds: Firmware: BCM43430/2 wl0: Oct  9 2020 14:44:32 version 9.88.4.65 (test) (f149b32@shgit)  (r679549) FWID 01-f40f3270
[  +0.113385] brcmfmac: brcmf_cfg80211_set_power_mgmt: power save enabled
```