Build with libtirpc on all architectures because glibc no longer provides
SunRPC support.

diff --git a/configure b/configure
--- a/configure
+++ b/configure
@@ -23635,10 +23635,13 @@
   *-pc-cygwin*)
     LIBS="$LIBS -ltirpc"
     CPPFLAGS="$CPPFLAGS -I/usr/include/tirpc"  ;;
+  *-linux-gnu)
+    LIBS="$LIBS -ltirpc"
+    CPPFLAGS="$CPPFLAGS"  ;;
   *) ;;
 esac
 
-if test "X$BUILD_XDR" != "Xyes"; then
+if test "X$BUILD_XDR" = "Xyes"; then
     cat confdefs.h - <<_ACEOF >conftest.$ac_ext
 /* end confdefs.h.  */
 
@@ -23693,9 +23696,9 @@
   ## but we need to make sure that it is present on the system. Do that here,
   ## The SunRPC of the glibc has been replaced by a TI-RPC (Transport Independent RPC) library for IPv6 support
   case "$host" in
-    *-pc-cygwin*)
+    *)
       HAVE_RPC="yes"
-      ac_fn_c_check_header_mongrel "$LINENO" "rpc.h" "ac_cv_header_rpc_h" "$ac_includes_default"
+      ac_fn_c_check_header_mongrel "$LINENO" "rpc/rpc.h" "ac_cv_header_rpc_h" "$ac_includes_default"
 if test "x$ac_cv_header_rpc_h" = xyes; then :
   :
 else
ref='/guix/'>summary</a><a href='/guix/refs/?id=f441a149b400d289224a78a7c13c8690080d0926'>refs</a><a class='active' href='/guix/log/etc/init.d'>log</a><a href='/guix/tree/etc/init.d?id=f441a149b400d289224a78a7c13c8690080d0926'>tree</a><a href='/guix/commit/etc/init.d?id=f441a149b400d289224a78a7c13c8690080d0926'>commit</a><a href='/guix/diff/etc/init.d?id=f441a149b400d289224a78a7c13c8690080d0926'>diff</a></td><td class='form'><form class='right' method='get' action='/guix/log/etc/init.d'>
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<div class='path'>path: <a href='/guix/log/?id=f441a149b400d289224a78a7c13c8690080d0926'>root</a>/<a href='/guix/log/etc?id=f441a149b400d289224a78a7c13c8690080d0926'>etc</a>/<a href='/guix/log/etc/init.d?id=f441a149b400d289224a78a7c13c8690080d0926'>init.d</a></div><div class='content'><table class='list nowrap'><tr class='nohover'><th class='left'>Age</th><th class='left'>Commit message (<a href='/guix/log/etc/init.d?id=f441a149b400d289224a78a7c13c8690080d0926&amp;showmsg=1'>Expand</a>)</th><th class='left'>Author</th></tr>
<tr><td><span title='2021-07-07 23:54:20 -0400'>2021-07-07</span></td><td><a href='/guix/commit/etc/init.d?id=4cbe0127a668cbcc64087c5d311308b59d39b104'>guix-install.sh: Prompt for configuring substitutes discovery.</a><span class='msg-avail'>...<span class='msg-tooltip'>Also ensure prompt_yes_no always print the message with a trailing space,
which is more pleasing to the eye.

* etc/guix-daemon.conf.in &lt;--discover=no&gt;: New guix-daemon option.
* etc/guix-daemon.service.in: Likewise.
* etc/init.d/guix-daemon.in: Likewise.
* etc/openrc/guix-daemon.in: Likewise.
* etc/guix-install.sh (configure_substitute_discovery): New procedure.
(sys_enable_guix_daemon): Ask the user whether automatic substitute discovery
should be enabled.  Set the '--discover' argument accordingly.
(prompt_yes_no): Add a trailing space to the message.
(sys_authorize_build_farms): Remove trailing space from the message argument.
* NEWS (Distribution): Add news.
</span></span></td><td>Maxim Cournoyer</td></tr>