sstate: Add extra intercept functions SSTATEPOSTCREATEFUNCS

sstate: Add extra intercept functions SSTATEPOSTCREATEFUNCS

In some cases we do either need to add extra sstate manipulation
functions, or change the existing modification functions. This patch
parametrizes it to SSTATEPOSTCREATEFUNCS after sstate_create_package

(From OE-Core rev: ed5fb9c69fcf0f6e8e98f72ac753c66119468ea5)

Signed-off-by: Hongxu Jia <hongxu.jia@windriver.com>
Signed-off-by: Saul Wold <sgw@linux.intel.com>
Signed-off-by: Ross Burton <ross.burton@intel.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>