[gnome-games] build: Fix running autogen.sh with $PWD != $srcdir

[Bastien Nocera <hadess src gnome org>]

commit bb30598d36bef2b0222877fceafab23b4bb54162
Author: Bastien Nocera <hadess hadess net>
Date:   Sun Jul 24 10:56:04 2016 +0200

    build: Fix running autogen.sh with $PWD != $srcdir
    
    As used by jhbuild by default nowadays.

 autogen.sh |    4 ++++
 1 files changed, 4 insertions(+), 0 deletions(-)
---
diff --git a/autogen.sh b/autogen.sh
index d13e030..8a2ddce 100755
--- a/autogen.sh
+++ b/autogen.sh
@@ -8,6 +8,8 @@ test -z "$srcdir" && srcdir=.
         exit 1
 }
 
+pushd "$srcdir"
+
 PKG_NAME=`autoconf --trace 'AC_INIT:$1' "$srcdir/configure.ac"`
 
 if [ "$#" = 0 -a "x$NOCONFIGURE" = "x" ]; then
@@ -25,6 +27,8 @@ intltoolize --force --copy --automake || exit 1
 autoreconf --verbose --force --install -Wno-portability || exit 1
 set +x
 
+popd
+
 if [ "$NOCONFIGURE" = "" ]; then
         set -x
         $srcdir/configure "$@" || exit 1