[gnome-documents] build: Fix getting-started installation

[Bastien Nocera <hadess src gnome org>]

commit 4ce7cf0aa711980579b7a97d15ed4b7bf6bb2e10
Author: Bastien Nocera <hadess hadess net>
Date:   Fri Jun 3 15:15:03 2016 +0200

    build: Fix getting-started installation
    
    With builddir != srcdir
    
    https://bugzilla.gnome.org/show_bug.cgi?id=767198

 m4/getting-started.m4 |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)
---
diff --git a/m4/getting-started.m4 b/m4/getting-started.m4
index 441522f..1de991f 100644
--- a/m4/getting-started.m4
+++ b/m4/getting-started.m4
@@ -109,7 +109,7 @@ install-pdfs:
          $(mkinstalldirs) "$(DESTDIR)$(HELP_DIR)/$$lc" || exit 1; \
        done
        @for lc in C $(_HELP_LINGUAS); do \
-         if test -f "$$lc/$(_HELP_OUTPUT)"; then d=; else d="$(srcdir)/"; fi; \
+         if test -f "$$lc/$(_HELP_OUTPUT)"; then d=; else d="$(builddir)/"; fi; \
          helpdir="$(DESTDIR)$(HELP_DIR)/$$lc/"; \
          if ! test -d "$$helpdir"; then $(mkinstalldirs) "$$helpdir"; fi; \
          echo "$(INSTALL_DATA) $$d$$lc/$(_HELP_OUTPUT) $$helpdir`basename $(_HELP_OUTPUT)`"; \