docs: Format comment timestamp in UTC

I just forgot '-u' in a54c9622860a.

Signed-off-by: Martin Kletzander <mkletzan@redhat.com>

diff --git a/docs/Makefile.am b/docs/Makefile.am
index a5bff7de1c9d5fb102637ecc964ac382b6ead467..34f84e526daafac002017e9bc9cf96affb902f93 100644 (file)
--- a/docs/Makefile.am
+++ b/docs/Makefile.am
@@ -198,9 +198,9 @@ MAINTAINERCLEANFILES = \
 
 timestamp="$(shell if test -n "$$SOURCE_DATE_EPOCH"; \
                   then \
-                    date --date="@$$SOURCE_DATE_EPOCH"; \
+                    date -u --date="@$$SOURCE_DATE_EPOCH"; \
                   else \
-                    date; \
+                    date -u; \
                   fi)"
 
 all-am: web