[gnome-builder] build: add -lm for IdeTaggedEntry

[Christian Hergert <chergert src gnome org>]

commit 796b66fd4497ba3a3f5ea2c1532a6beadbcd1738
Author: Christian Hergert <chergert redhat com>
Date:   Wed Apr 4 14:09:05 2018 -0700

    build: add -lm for IdeTaggedEntry

 src/libide/meson.build | 1 +
 1 file changed, 1 insertion(+)
---
diff --git a/src/libide/meson.build b/src/libide/meson.build
index b3e29ded3..be028128d 100644
--- a/src/libide/meson.build
+++ b/src/libide/meson.build
@@ -202,6 +202,7 @@ libide_deps = [
   libgtksource_dep,
   libjson_glib_dep,
   libjsonrpc_glib_dep,
+  libm_dep,
   libpangoft2_dep,
   libpeas_dep,
   libtemplate_glib_dep,