Fix mask/unmask game

We want to be able to mask packages from binhost repo even.

package_mask.conf.d/binhost.conf

@@ -1 +1,3 @@
-*/*
+# mask all non-binhost packages
+*/*::gentoo
+*/*::libressl

package_unmask.conf.d/binhost.conf

@@ -1,5 +1,3 @@
-*/*::gentoo-binhost
-
 # these don't trigger actual builds, so it's safe to install
 # on the client machines
 sys-kernel/vanilla-sources