I'm mostly writing this as an assumption, so note I may be incorrect.
Enter your terminal. Type mkdir /mnt/ to create the mount directory. Thereafter mount your root partition to /mnt. mount /dev/(partition) /mnt.
Enable swap if you have a swap partition. swapon /dev/(partition).
Finally, chroot /mnt
From there you should just be able to type sudo clr-boot-manager update to update your boot loader with whatever Solus had before it was wiped.
That should recreate Solus' boot entry, though I'm not 100% certain if it'll retain Aerys, as I'm mostly unfamiliar with the specifics of clr-boot-manager.
