Mozilla now publishing Firefox builds for AARCH64

[CNK]

Just mentioning that Mozilla are now publishing Nightly builds of Firefox for ARM AARCH64 and planning to introduce AARCH64 builds of all their releases later on. I haven't tried to run one myself, but this should be useful for people looking to run current versions of Firefox on 64-bit PiCore without waiting for a new firefox.tcz extension to be made. When they start doing it for normal (non-nightly) builds, it should be possible to modify the firefox_getLatest.sh script to download the AARCH64 builds in PiCore.