package_deb.bbclass/package_ipk.bbclass: sort RPROVIDES

package_deb.bbclass/package_ipk.bbclass: sort RPROVIDES

The dict.fromkeys() creates a dict without order, there might be a
problem when build the same recipe again, for example:

- First build of make:
  Provides: es-translation, make-locale
- Second build of acl:
  Provides: make-locale, es-translation

They are exactly the same Provides, but tools like "diff" doesn't think
so. Sort RPROVIDES will fix the problem.

Signed-off-by: Robert Yang <liezhi.yang@windriver.com>
Signed-off-by: Ross Burton <ross.burton@intel.com>