Fix cs_interesting_for_ipcp_p wrt flag_profile_partial_training.

Fix cs_interesting_for_ipcp_p wrt flag_profile_partial_training.

As noticed by Martin Jambor, I introduced a bug while simplifying
cs_interesting_for_ipcp_p and reversed condition for
flag_profile_partial_training.  Also I noticed that we probably want to
consider calls with unintialized counts for cloning so the pass does somehting
with -fno-guess-branch-probability even thugh this is probably not very useful
in practice.

gcc/ChangeLog:

	* ipa-cp.cc (cs_interesting_for_ipcp_p): Fix handling of uninitialized
	counts and 0 IPA cost wrt flag_profile_partial_training.