sci-libs/nlopt: Revbump post dep change

Signed-off-by: Michał Górny <mgorny@gentoo.org>

diff --git a/sci-libs/nlopt/nlopt-2.4.2-r1.ebuild b/sci-libs/nlopt/nlopt-2.4.2-r2.ebuild
similarity index 100%
rename from sci-libs/nlopt/nlopt-2.4.2-r1.ebuild
rename to sci-libs/nlopt/nlopt-2.4.2-r2.ebuild