Yes, in order to be able to unload the ahci builtin kernel module, I should compile a new kernel with a custom config (making the module as loadable and not as builtin).
So, Is there any way to skip the kernel packages updates?
Yes, the kernel is there as part of the kernel package, like linux58 + maybe meta package like linux-latest.
If you remove them, then your updates will not pick them up but be careful you need to not forget to do the mkinitcpio stuff to regenerate the ramdisks, and if you have grub then some tweaking might also be needed.