[gnumeric] Docs: fix install problem.

[Morten Welinder <mortenw src gnome org>]

commit 1fce7ad2c5d22ecb798c99034687663c0d071ed8
Author: Morten Welinder <terra gnome org>
Date:   Thu Aug 25 09:09:56 2016 -0400

    Docs: fix install problem.

 doc/Makefile.am |    1 +
 1 files changed, 1 insertions(+), 0 deletions(-)
---
diff --git a/doc/Makefile.am b/doc/Makefile.am
index 87d0451..fbd7f37 100644
--- a/doc/Makefile.am
+++ b/doc/Makefile.am
@@ -526,6 +526,7 @@ HELP_MEDIA= \
 install-exec-hook:
        for d in C $(HELP_LINGUAS); do \
                helpdir="$(HELP_DIR)/$$d/$(HELP_ID)"; \
+               install -d $$helpdir; \
                $(RM) $$helpdir/index.docbook; \
                $(LN_S) gnumeric.xml $$helpdir/index.docbook; \
        done