Fix the DISABLE_JIT build.

mono/mini/tramp-arm.c

@@ -1038,6 +1038,15 @@ mono_arch_get_gsharedvt_arg_trampoline (MonoDomain *domain, gpointer arg, gpoint
 	return start;
 }
 
+#else
+
+gpointer
+mono_arch_get_gsharedvt_arg_trampoline (MonoDomain *domain, gpointer arg, gpointer addr)
+{
+	g_assert_not_reached ();
+	return NULL;
+}
+
 #endif
 
 #if defined(MONOTOUCH) || defined(MONO_EXTENSIONS)