Remove dead code from `link_rust.sh`

[jyn514]

rust-lang/rust#103286 was never merged and rust-lang/rust#101961 (comment) is blocked.

simpleinfra/ansible/roles/dev-desktop/files/scripts/link_rust.sh

Lines 25 to 26 in 75573f9

	if [ "$bootstrap_version" -gt 2 ]; then
	stages=(stage1-sysroot stage2-sysroot)