[gnome-system-monitor] We don't need anymore the CFLAGS gnu89. Compilers are modern enough.

[Benoît Dejean <bdejean src gnome org>]

commit 258ea1153bd5e7f54351fad025d8a994b21dd9be
Author: Benoît Dejean <bdejean gmail com>
Date:   Sun Aug 2 06:38:47 2015 +0200

    We don't need anymore the CFLAGS gnu89.
    Compilers are modern enough.

 configure.ac |    1 -
 1 files changed, 0 insertions(+), 1 deletions(-)
---
diff --git a/configure.ac b/configure.ac
index 2cbcfa5..9a958f1 100644
--- a/configure.ac
+++ b/configure.ac
@@ -95,7 +95,6 @@ if test "$GCC" = "yes" -a "$set_more_warnings" != "no"; then
     -Wchar-subscripts -Wmissing-declarations -Wmissing-prototypes \
     -Wnested-externs -Wpointer-arith \
     -Wcast-align -Wsign-compare \
-    -std=gnu89 \
     $CFLAGS"
     CXXFLAGS="-Wall $CXXFLAGS"
 else