Sync from upstream gnulib and autoconf.

diff --git a/gnulib b/gnulib
index b48afd89ec9be56156d6e2bebfdf457c778fe5c3..54a0a8a701799773538cdb6880c6385137c13684 160000 (submodule)
--- a/gnulib
+++ b/gnulib
@@ -1 +1 @@
-Subproject commit b48afd89ec9be56156d6e2bebfdf457c778fe5c3
+Subproject commit 54a0a8a701799773538cdb6880c6385137c13684

diff --git a/submodules/autoconf b/submodules/autoconf
index 81074eaa201a289d11b6be05e0c78afbe5ff79f5..2b0d95faef68d7ed7c08b0edb9ff1c38728376fa 160000 (submodule)
--- a/submodules/autoconf
+++ b/submodules/autoconf
@@ -1 +1 @@
-Subproject commit 81074eaa201a289d11b6be05e0c78afbe5ff79f5
+Subproject commit 2b0d95faef68d7ed7c08b0edb9ff1c38728376fa