[gnome-applets] configure.ac: fix 'no AC_LANG_SOURCE call detected in body' warning

[Alberts Muktupāvels <muktupavels src gnome org>]

commit ef98b77b486220b692f4480043180ec0183e0128
Author: Alberts Muktupāvels <alberts muktupavels gmail com>
Date:   Sun Sep 27 20:43:15 2015 +0300

    configure.ac: fix 'no AC_LANG_SOURCE call detected in body' warning

 configure.ac |   17 +++++++++--------
 1 files changed, 9 insertions(+), 8 deletions(-)
---
diff --git a/configure.ac b/configure.ac
index 0c9c767..be99be7 100644
--- a/configure.ac
+++ b/configure.ac
@@ -230,16 +230,17 @@ AC_SUBST(UPOWER_LIBS)
 AC_SUBST(LIBM)
 
 dnl -- check for wirelesstools (optional) -------------------------------------
- 
+
 ac_have_iwevgenie=no
 AC_MSG_CHECKING([for wireless-tools >= 28pre9])
-AC_COMPILE_IFELSE([
-               #include <iwlib.h>
-                 #ifndef IWEVGENIE
-                 #error "not found"
-                 #endif],
-                ac_have_iwevgenie=yes
-)
+
+
+AC_COMPILE_IFELSE([AC_LANG_SOURCE([
+       #include <iwlib.h>
+       #ifndef IWEVGENIE
+       #error "not found"
+       #endif
+])], [ac_have_iwevgenie=yes])
 AC_MSG_RESULT([$ac_have_iwevgenie])
 if test "$ac_have_iwevgenie" = yes; then
          AC_DEFINE(HAVE_IW, 1, [Defined if you have wirelesstools])