ash supports this just fine, and the benefits outweigh 100% POSIX
compatibility.

Setting MAC may only be supported on either WLAN or Bluetooth on some
systems.

Something must have gone wrong with the previous commit

Be compatible with any POSIX shell

Run shellcheck on every merge request.

Manufacturer OUI lookup is removed

Read rfkill state of Bluetooth and WLAN interfaces before setting
the MAC address. After setting the MAC address, restore the saved
rfkill state.

Fixes https://gitlab.com/postmarketOS/bootmac/-/issues/2

qmac was renamed to bootmac

Use 02:00 to specify that we generate a local administered
address as MAC address. This approach is used by all MSM8916 devices.

Fixes https://gitlab.com/postmarketOS/bootmac/-/issues/1

qmac was renamed too bootmac

Bootmac configures the MAC addresses of WLAN and Bluetooth interfaces at boot.
Bootmac can be invoked in various ways at boot, but currently only udev rules are tested.
Bootmac generates MAC addresses from the `serialno` provided by Android bootloaders
through /proc/cmdline or from /etc/machine-id. The Organizationally Unique Identifier (OUI)
is retrieved from a lookup database macdb by matching deviceinfo_manufacturer
from /etc/deviceinfo with the entries in the database.