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   ## The SunRPC of the glibc has been replaced by a TI-RPC (Transport Independent RPC) library for IPv6 support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
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