rpm: fix multilib macro installation

rpm: fix multilib macro installation

For now, the rpm macro for multilib is not installed correctly. For
example, in x86-64 lib32 situation, the macro is installed under
tmp/work/x86-pokymllib32-linux/rpm/5.4.16-r0/image/usr/lib/rpm/poky/i686-linux/.

The directory is even not under WORKDIR. And it will of course not be
packaged.

We need to save necessary values before updating the localdata and restore
them so that the macros could be installed into the correct directory.

Signed-off-by: Chen Qi <Qi.Chen@windriver.com>