depgraph: fix missed atom_not_selected initialization (bug 612846)

Fix the _slot_operator_update_probe method to ensure that the
atom_not_selected variable is always properly initialized. This
problem prevented the method from identifying slot operator rebuild
candidates, leading to dependency conflicts and/or missed updates.
For example, this may have triggered the missed llvm update reported
in bug 611742, since these dependencies from the mesa-17.0.1 ebuild
are capable of triggering the problem, when atom_not_selected is not
properly set to True for the second atom:

	|| (
		sys-devel/llvm:4[${MULTILIB_USEDEP}]
		>=sys-devel/llvm-3.6.0:0[${MULTILIB_USEDEP}]
	)

X-Gentoo-bug: 612846
X-Gentoo-bug-url: https://bugs.gentoo.org/show_bug.cgi?id=612846
Acked-by: Brian Dolbec <dolsen@gentoo.org>
1 file changed