[multicast] prevent VLAN translation via match key enforcement

.cargo/config.toml

@@ -6,3 +6,7 @@ xtask = "run --package xtask --"
 # See https://doc.rust-lang.org/cargo/reference/config.html#target.
 [build]
 rustflags = ["--cfg", "tokio_unstable"]
+
+# Workaround for omicron's bootstore transitive dependency on pq-sys
+[env]
+DEP_PQ_LIBDIRS = "1"