powerpc/pseries: Split processor entitlement retrieval and gathering to helper routines

Split the retrieval and setting of processor entitlement and weight into
helper routines.  This also removes the printing of the raw values
returned from h_get_ppp, the values are already parsed and printed.

Signed-off-by: Nathan Fontenot <nfont@austin.ibm.com>
Signed-off-by: Robert Jennings <rcj@linux.vnet.ibm.com>
Acked-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>