Use new stat item/ctr getter APIs

Generated with spatch:
"""
@@
expression E1, E2;
@@
- &E2->ctr[E1]
+ rate_ctr_group_get_ctr(E2, E1)
"""

Change-Id: I594c08b8fe0ed54a31353d8c6c911cc7293ae7c0
2 files changed