remove a bashism ...

git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@22357 65c4cc65-6c06-0410-ace0-fbb531ad65f3

bootstrap.sh

@@ -22,8 +22,10 @@ then
 	autoheader259
 	automake19 --add-missing --copy 2>/dev/null
 else
-	export AUTOCONF_VERSION=2.59
-	export AUTOMAKE_VERSION=1.9
+	AUTOCONF_VERSION=2.59
+	AUTOMAKE_VERSION=1.9
+	export AUTOCONF_VERSION
+	export AUTOMAKE_VERSION
 
 	check_for_app autoconf
 	check_for_app autoheader