build(Makefile): drop init/rsh deps from iso target

iso only needs the kernel binary and Limine files. init and rsh are
userspace binaries copied to disk.img for local runs; they are not
part of the bootable ISO and unavailable in CI (rsh lives in a
separate repo). Removes the ../rsh/Cargo.toml not found CI failure.

Author: gitcomit8

Makefile

@@ -46,7 +46,7 @@ rsh:
 	    --release \
 	    --target x86_64-unknown-none
 
-iso: init rsh $(ISO_ROOT)/boot/kernel $(ISO_ROOT)/boot/limine-bios.sys $(ISO_ROOT)/boot/limine-bios-cd.bin $(ISO_ROOT)/boot/limine-uefi-cd.bin $(ISO_ROOT)/limine.conf
+iso: $(ISO_ROOT)/boot/kernel $(ISO_ROOT)/boot/limine-bios.sys $(ISO_ROOT)/boot/limine-bios-cd.bin $(ISO_ROOT)/boot/limine-uefi-cd.bin $(ISO_ROOT)/limine.conf
 	xorriso -as mkisofs -b boot/limine-bios-cd.bin \
 	  -no-emul-boot -boot-load-size 4 -boot-info-table \
 	  --efi-boot boot/limine-uefi-cd.bin \