New option --with-included-argp

@@ -337,8 +337,14 @@ MU_CHECK_FUNCS(strtok_r getline strndup strnlen strchrnul)
 MU_CHECK_UTMP
 
 dnl Check for libraries
-AC_CHECK_FUNCS(argp_parse, :,
-               [
+USE_INCLUDED_ARGP=
+AC_ARG_WITH([included-argp],
+            AC_HELP_STRING([--with-included-argp],
+                           [Use included argp library]),
+            [USE_INCLUDED_ARGP=${withval}],
+            [AC_CHECK_FUNCS(argp_parse, :, [USE_INCLUDED_ARGP=yes])])
+
+if test $USE_INCLUDED_ARGP = yes; then
        MU_LIBOBJ(argp-ba)
        MU_LIBOBJ(argp-eexst)
        MU_LIBOBJ(argp-fmtstream)
@@ -349,7 +355,7 @@ AC_CHECK_FUNCS(argp_parse, :,
        MU_LIBOBJ(argp-pvh)
        MU_LIBOBJ(argp-xinl)
        MU_LIBOBJ(pin)
-	       ])
+fi
 
 AC_MSG_CHECKING(whether extern program_invocation_name is present)
 AC_TRY_COMPILE([#include <argp.h>