libtool: use AS_HELP_STRING in LT_WITH_SYSROOT help message.

This patch fixes so help output is formatted similar with
other macros using AS_HELP_STRING. Also it outputs '[=DIR]'
as I suspect intended rather than '=DIR'.

diff --git a/m4/libtool.m4 b/m4/libtool.m4
index 195348c2bad65a69f7f7ef97fccdf20e50c872b1..262922bee79517998524533ea4a8fd4fd2f064e3 100644 (file)
--- a/m4/libtool.m4
+++ b/m4/libtool.m4
@@ -1220,8 +1220,9 @@ _LT_DECL([], [ECHO], [1], [An echo program that protects backslashes])
 AC_DEFUN([_LT_WITH_SYSROOT],
 [AC_MSG_CHECKING([for sysroot])
 AC_ARG_WITH([sysroot],
-[  --with-sysroot[=DIR] Search for dependent libraries within DIR
-                        (or the compiler's sysroot if not specified).],
+[AS_HELP_STRING([--with-sysroot@<:@=DIR@:>@],
+  [Search for dependent libraries within DIR (or the compiler's sysroot
+   if not specified).])],
 [], [with_sysroot=no])
 
 dnl lt_sysroot will always be passed unquoted.  We quote it here