Misc hard link fixes

I searched the various classes and looked for copies that should attempt to
preserve hardlinks.  This fixes the majority of this copies by switching to
using tar as the copy method.  It also has the side effect of preserving sparse
files.

Signed-off-by: Mark Hatle <mark.hatle@windriver.com>

meta/classes/sourcepkg.bbclass

@@ -41,7 +41,7 @@ sourcepkg_do_create_orig_tgz(){
 	echo $src_tree
 	oenote "Creating .orig.tar.gz in ${DEPLOY_DIR_SRC}/${P}.orig.tar.gz"
 	tar cvzf ${DEPLOY_DIR_SRC}/${P}.orig.tar.gz --exclude-from temp/exclude-from-file $src_tree
-	cp -pPR $src_tree $src_tree.orig
+	tar -cf - -C $src_tree -ps . | tar -xf - -C $src_tree.orig
 }
 
 sourcepkg_do_archive_bb() {