Update nmodl to latest master (#298)

iomaganaris · web-flow · commit 94ede63e1083 · 2020-04-28T21:07:18.000+02:00
diff --git a/external/nmodl b/external/nmodl
@@ -1 +1 @@
-Subproject commit 25e654cd0334e77ef7e15a600dbc564f58862e64
+Subproject commit 622fe588028e2279c3814208a4547568512c3bec
