objtool: Remove annotate_{,un}reachable()

objtool: Remove annotate_{,un}reachable()

[ Upstream commit 06e24745985c8dd0da18337503afcf2f2fdbdff1 ]

There are no users of annotate_reachable() left.

And the annotate_unreachable() usage in unreachable() is plain wrong;
it will hide dangerous fall-through code-gen.

Remove both.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Josh Poimboeuf <jpoimboe@kernel.org>
Link: https://lore.kernel.org/r/20241128094312.235637588@infradead.org
Stable-dep-of: 73cfc53cc3b6 ("objtool: Fix C jump table annotations for Clang")
Signed-off-by: Sasha Levin <sashal@kernel.org>