Depend on SOURCE_DATE_EPOCH for manpage generation

The date for the manpage is provided by the build system, which
ensures the build is repeatable.

Author: minfrin

Makefile.am

@@ -7,10 +7,6 @@ retry_SOURCES = retry.c
 EXTRA_DIST = retry.spec
 dist_man_MANS = retry.1
 
-dist-hook:
-	./retry --help | txt2man -d 1 -t "${PACKAGE_NAME}" -r "${PACKAGE_NAME}-${PACKAGE_VERSION}" > retry.1
-	install retry.1 $(distdir)/retry.1
-
-retry.1: | retry
-	./retry --help | txt2man -d 1 -t "${PACKAGE_NAME}" -r "${PACKAGE_NAME}-${PACKAGE_VERSION}" > retry.1
+retry.1: retry
+	./retry --help | txt2man -s 1 -t "${PACKAGE_NAME}" -r "${PACKAGE_NAME}-${PACKAGE_VERSION}" > retry.1