Support other initrd generators

[Cornelicorn]

Hi,
the linux-aarch64 package currently hard-depends on mkinitcpio. This means if you install the kernel along with dracut, you will get an unnecessary initrd build, which can slow down older devices a lot.
Could this be adjusted to depend on initramfs like on x86_64 and having mkinitcpio and dracut provide initramfs?

[sehraf]

i second that