[beast: 1/8] DOCS: allow to skip documentation rebuilds with "NODOC=1 make"

[Tim Janik <timj src gnome org>]

commit eace4283c2abf5e590a524931fcf8ad511c1503c
Author: Tim Janik <timj gnu org>
Date:   Thu Aug 27 01:20:39 2015 +0200

    DOCS: allow to skip documentation rebuilds with "NODOC=1 make"

 docs/Makefile.am |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)
---
diff --git a/docs/Makefile.am b/docs/Makefile.am
index d1ceccd..231487b 100644
--- a/docs/Makefile.am
+++ b/docs/Makefile.am
@@ -32,7 +32,7 @@ uninstall-local:
 # == html/ build rules ==
 include Makefile.doxygen
 git_index_file = $(shell test ! -x $(top_srcdir)/.git/ || echo $(top_srcdir)/.git/index)
-html/doc-version: @INGIT@ $(git_index_file)    # conditionally rebuild, depending on HEAD changes
+html/doc-version: @INGIT@ $(if $(NODOC),, $(git_index_file)) # conditionally rebuild, depending on HEAD 
changes
        $(AM_V_GEN)
        $(Q) test -e $@ && test "`cat $ `" = "$(DOC_VERSION)" \
        || $(MAKE) $(AM_MAKEFLAGS) --no-print-directory html-docs