[rygel] build: Replace another cp -d

[Jens Georg <jensgeorg src gnome org>]

commit fdd2dc1394864c3ae621e944daa6756711947da9
Author: Jens Georg <mail jensge org>
Date:   Mon Mar 17 19:46:30 2014 +0100

    build: Replace another cp -d
    
    Signed-off-by: Jens Georg <mail jensge org>

 doc/reference/doc-build.am |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)
---
diff --git a/doc/reference/doc-build.am b/doc/reference/doc-build.am
index ab95f1d..de896d9 100644
--- a/doc/reference/doc-build.am
+++ b/doc/reference/doc-build.am
@@ -72,7 +72,7 @@ install-data-hook: gtkdoc/html/index.html
 else
 install-data-hook:
        test -d $(srcdir)/gtkdoc/html && $(MKDIR_P) $(RYGEL_GTKDOC_INSTALL_DIR); true
-       test -d $(srcdir)/gtkdoc/html && cp -d -R $(srcdir)/gtkdoc/html/* $(RYGEL_GTKDOC_INSTALL_DIR); true
+       test -d $(srcdir)/gtkdoc/html && cp -p -R $(srcdir)/gtkdoc/html/* $(RYGEL_GTKDOC_INSTALL_DIR); true
        test -d $(srcdir)/gtkdoc/html && chmod -R u+w $(RYGEL_GTKDOC_INSTALL_DIR); true
 
 endif