app-accessibility/rhvoice-core: add missing dep

Closes: https://bugs.gentoo.org/923877
Signed-off-by: Anna (cybertailor) Vyalkova <cyber+gentoo@sysrq.in>

app-accessibility/rhvoice-core/rhvoice-core-1.14.0-r1.ebuild

@@ -25,6 +25,7 @@ SLOT="0"
 REQUIRED_USE="|| ( ao portaudio pulseaudio )"
 
 COMMON_DEPEND="
+	dev-libs/boost:=
 	ao? ( media-libs/libao )
 	dbus? (
 		dev-libs/glib:2[dbus]