configure.ac: fix minor output ordering issue

Put Perl test below the section title.

Signed-off-by: Jeff Squyres <jsquyres@cisco.com>

configure.ac

@@ -70,13 +70,14 @@ OPAL_LOAD_PLATFORM
 # Start it up
 #
 
+OPAL_CONFIGURE_SETUP
+opal_show_title "Configuring project_name_long"
+opal_show_subtitle "Prerequisites"
+
 AC_CHECK_PROG([PERL],[perl],[perl],[no])
 AS_IF([test "X$PERL" = "Xno"],
       [AC_MSG_ERROR(["Open MPI requires perl. Aborting"])])
 
-OPAL_CONFIGURE_SETUP
-opal_show_title "Configuring project_name_long"
-
 #
 # Setup some things that must be done before AM-INIT-AUTOMAKE
 #