Build on OpenBSD

Index: meson.build
--- meson.build.orig
+++ meson.build
@@ -19,11 +19,12 @@ add_project_arguments(
 cc = meson.get_compiler('c')
 
 cairo               = dependency('cairo')
+epoll_shim	    = dependency('epoll-shim')
 glib                = dependency('glib-2.0')
 gobject             = dependency('gobject-2.0')
 pango               = dependency('pango')
 pangocairo          = dependency('pangocairo')
-rt                  = cc.find_library('rt')
+# rt                  = cc.find_library('rt')
 wayland_client      = dependency('wayland-client')
 wayland_protos      = dependency('wayland-protocols')
 wayland_scanner_dep = dependency('wayland-scanner')
@@ -61,11 +62,12 @@ endforeach
 
 dmenu_deps = [
   cairo,
+  epoll_shim,
   glib,
   gobject,
   pango,
   pangocairo,
-  rt,
+#  rt,
   wayland_client,
   xkbcommon
 ]