[POWERPC] pseries: phyp dump: Tracking memory range freed

This tracks the size freed.  For now it does a simple rudimentary
calculation of the ranges freed.  The idea is to keep it simple at the
external shell script level and send in large chunks for now.

Signed-off-by: Manish Ahuja <mahuja@us.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>