Add the new MPM to the build system as an alternative to the other MPMs
and add itk's dependency to libcap.

--- a/server/mpm/config2.m4
+++ b/server/mpm/config2.m4
@@ -1,7 +1,7 @@
 AC_MSG_CHECKING(which MPM to use by default)
 AC_ARG_WITH(mpm,
 APACHE_HELP_STRING(--with-mpm=MPM,Choose the process model for Apache to use by default.
-                          MPM={event|worker|prefork|winnt}
+                          MPM={event|worker|prefork|winnt|itk}
                           This will be statically linked as the only available MPM unless
                           --enable-mpms-shared is also specified.
 ),[
@@ -66,6 +66,9 @@
     else
         AC_MSG_ERROR([MPM $i is not supported on this platform.])
     fi
+    if test "$i" = "itk" ; then
+        AC_CHECK_LIB(cap, cap_init)
+    fi
 done
 
 if test $mpm_build = "shared"; then
--- a/modules/arch/unix/config5.m4
+++ b/modules/arch/unix/config5.m4
@@ -3,6 +3,7 @@
 
 if ap_mpm_is_enabled "worker" \
    || ap_mpm_is_enabled "event" \
+   || ap_mpm_is_enabled "itk" \
    || ap_mpm_is_enabled "prefork"; then
     unixd_mods_enable=yes
 else
