mk: fix permissions when using make install

When using make install, the permissions of the resulting file should be
those of the user using make install, not those of the user who ran the
build. This would not be the case when a user explicitly runs:

   "make && sudo make install"

Fix this by changing "cp -a", which preserves all attributes, to
"cp -dR --preserve=timestamp", and by adding the flags
"--no-same-owner --no-same-permissions" to the calls to tar.

Fixes: 1fa0fd9d6b42 ("mk: allow to specify DESTDIR in build rule")
Fixes: 6b62a72a70d0 ("mk: install a standard cutomizable tree")
Fixes: 576de42b83e5 ("doc: render and install man pages")
Cc: stable@dpdk.org
Signed-off-by: Bruce Richardson <bruce.richardson@intel.com>
Acked-by: Thomas Monjalon <thomas@monjalon.net>