build-sys: force creation of symlink

For some reason make sometimes wants to rerun this, and
ln would refuse to recreate the link.

diff --git a/Makefile.am b/Makefile.am
index 7b1bac5e5072e19594cdc57e2cd7c8e67264b6cd..7e408798a62cf9eb06107900f7b31d58c1de2e15 100644 (file)
--- a/Makefile.am
+++ b/Makefile.am
@@ -522,7 +522,7 @@ CLEANFILES += \
        man/index.html
 
 man/index.html:
-       $(AM_V_GEN)$(LN_S) systemd.index.html $@
+       $(AM_V_GEN)$(LN_S) -f systemd.index.html $@
 
 NON_INDEX_XML_FILES = $(filter-out man/systemd.index.xml,$(XML_FILES))