Revert http://git.php.net/?p=php-src.git;a=patch;h=1c0fccfc9abaaea02ae717547bc3b69fcb2de86c

diff -up php-5.6.0beta2/sapi/phpdbg/config.m4.readline php-5.6.0beta2/sapi/phpdbg/config.m4
--- php-5.6.0beta2/sapi/phpdbg/config.m4.readline	2014-05-03 08:36:56.693265559 +0200
+++ php-5.6.0beta2/sapi/phpdbg/config.m4	2014-05-03 08:37:56.542512577 +0200
@@ -20,10 +20,6 @@ if test "$PHP_PHPDBG" != "no"; then
   PHP_PHPDBG_CFLAGS="-D_GNU_SOURCE"
   PHP_PHPDBG_FILES="phpdbg.c phpdbg_parser.c phpdbg_lexer.c phpdbg_prompt.c phpdbg_help.c phpdbg_break.c phpdbg_print.c phpdbg_bp.c phpdbg_opcode.c phpdbg_list.c phpdbg_utils.c phpdbg_info.c phpdbg_cmd.c phpdbg_set.c phpdbg_frame.c phpdbg_watch.c phpdbg_btree.c"
 
-  if test "$PHP_READLINE" != "no"; then
-  	PHPDBG_EXTRA_LIBS="-lreadline"
-  fi
-  
   PHP_SUBST(PHP_PHPDBG_CFLAGS)
   PHP_SUBST(PHP_PHPDBG_FILES)
   PHP_SUBST(PHPDBG_EXTRA_LIBS)