linux-firmware: split qca firmwares in separate packages

linux-firmware: split qca firmwares in separate packages

This patch introduces the following packages for firmwares under qca/:

- linux-firmware-qca-qca61x4
- linux-firmware-qca-wcn3988
- linux-firmware-qca-wcn399x
- linux-firmware-qca-wcn6750
- linux-firmware-qca-qca2066
- linux-firmware-qca-wcn7850
- linux-firmware-qca-misc: catches all firmwares that are not already
  included in the other -qca- packages (currently empty).

linux-firmware-qca is now a meta package that depends on all of the
split-out qca packages.

Note: Content of the FILES:${PN}-qca* variables taken from WHENCE.

Signed-off-by: Marc Ferland <marc.ferland@sonatest.com>
Signed-off-by: Mathieu Dubois-Briand <mathieu.dubois-briand@bootlin.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>