[epiphany] configure: Remove unused check

[Michael Catanzaro <mcatanzaro src gnome org>]

commit 28c3fa5ecd3535f0acdfea7123d13746ac7bf26a
Author: Michael Catanzaro <mcatanzaro gnome org>
Date:   Thu Oct 13 21:41:03 2016 -0500

    configure: Remove unused check

 configure.ac |    6 ------
 1 files changed, 0 insertions(+), 6 deletions(-)
---
diff --git a/configure.ac b/configure.ac
index 5039a3a..cca9bfe 100644
--- a/configure.ac
+++ b/configure.ac
@@ -129,12 +129,6 @@ PKG_CHECK_MODULES([WEBKIT2GTK_WEB_EXTENSION], [webkit2gtk-web-extension-4.0 >= $
 AC_CHECK_HEADERS([execinfo.h])
 AC_SEARCH_LIBS([backtrace], [c execinfo])
 
-# ***************
-# Multimedia keys
-# ***************
-
-AC_CHECK_HEADERS([X11/XF86keysym.h])
-
 # *******************************
 # Internationalization
 # *******************************