Remove configure option --enable-phpdbg-readline

Readline support in sapi/phpdbg can be determined automatically during
the build process whether ext/readline is enabled and built statically.

Author: petk

UPGRADING.INTERNALS

@@ -46,6 +46,9 @@ PHP 8.4 INTERNALS UPGRADE NOTES
 
  b. Unix build system changes
    - The configure option --with-zlib-dir has been removed.
+   - The configure option --enable-phpdbg-readline has been removed. Readline
+     support in sapi/phpdbg is determined automatically whether ext/readline is
+     enabled and built statically.
    - COOKIE_IO_FUNCTIONS_T symbol has been removed (use cookie_io_functions_t).
    - HAVE_SOCKADDR_UN_SUN_LEN symbol renamed to HAVE_STRUCT_SOCKADDR_UN_SUN_LEN.
    - PHP_CHECK_IN_ADDR_T M4 macro and 'in_addr_t' fallback definition to 'u_int'

sapi/phpdbg/config.m4

@@ -12,13 +12,6 @@ PHP_ARG_ENABLE([phpdbg-debug],
   [no],
   [no])
 
-PHP_ARG_ENABLE([phpdbg-readline],
-  [for phpdbg readline support],
-  [AS_HELP_STRING([--enable-phpdbg-readline],
-    [Enable readline support in phpdbg (depends on static ext/readline)])],
-  [no],
-  [no])
-
 if test "$PHP_PHPDBG" != "no"; then
   AC_HEADER_TIOCGWINSZ
   AC_DEFINE(HAVE_PHPDBG, 1, [ ])
@@ -32,17 +25,21 @@ if test "$PHP_PHPDBG" != "no"; then
   PHP_PHPDBG_CFLAGS="-D_GNU_SOURCE -DZEND_ENABLE_STATIC_TSRMLS_CACHE=1"
   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_list.c phpdbg_utils.c phpdbg_info.c phpdbg_cmd.c phpdbg_set.c phpdbg_frame.c phpdbg_watch.c phpdbg_btree.c phpdbg_sigsafe.c phpdbg_io.c phpdbg_out.c"
 
-  AC_MSG_CHECKING([for phpdbg and readline integration])
-  if test "$PHP_PHPDBG_READLINE" = "yes"; then
-    if test "$PHP_READLINE" != "no" -o  "$PHP_LIBEDIT" != "no"; then
-  	  AC_DEFINE(HAVE_PHPDBG_READLINE, 1, [ ])
-  	  PHPDBG_EXTRA_LIBS="$PHP_READLINE_LIBS"
-  	  AC_MSG_RESULT([ok])
-  	else
-  	  AC_MSG_RESULT([readline is not available])
-    fi
+  AC_MSG_CHECKING([for readline integration in phpdbg])
+  if test -n "$with_readline" && test "$with_readline" != "no"; then
+    AS_CASE([$with_readline],
+      [shared,*|shared],[AC_MSG_RESULT([disabled (depends on static ext/readline)])],[
+      AC_MSG_RESULT([yes, readline])
+      PHP_PHPDBG_CFLAGS="$PHP_PHPDBG_CFLAGS -DHAVE_PHPDBG_READLINE"
+    ])
+  elif test -n "$with_libedit" && test "$with_libedit" != "no"; then
+    AS_CASE([$with_libedit],
+      [shared,*|shared],[AC_MSG_RESULT([disabled (depends on static ext/readline)])],[
+      AC_MSG_RESULT([yes, libedit])
+      PHP_PHPDBG_CFLAGS="$PHP_PHPDBG_CFLAGS -DHAVE_PHPDBG_READLINE"
+    ])
   else
-    AC_MSG_RESULT([disabled])
+    AC_MSG_RESULT([disabled (depends on static ext/readline)])
   fi
 
   AC_CACHE_CHECK([for userfaultfd faulting on write-protected memory support], ac_cv_phpdbg_userfaultfd_writefault, AC_COMPILE_IFELSE([AC_LANG_SOURCE([[