perf map: Add set_ methods for...

perf map: Add set_ methods for map->{start,end,pgoff,pgoff,reloc,erange_warned,dso,map_ip,unmap_ip,priv}

To have a way to intercept usage of the reference counted struct map.

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>