Allow ampersand calls to CORE subs with (_) proto

Allow ampersand calls to CORE subs with (_) proto

This commit adds all subs with a (_) prototype to the list of those
that can be called with ampersand syntax or through references.  These
have bodies like this:

$ ./perl -Ilib -MO=Concise,CORE::abs -e 'BEGIN{\&CORE::abs}'
CORE::abs:
3  <1> leavesub[1 ref] K/REFC,1 ->(end)
2     <1> abs[t1] sK/1 ->3
1        <$> coreargs(IV 111) s ->2
-e syntax OK

coreargs fetches the caller’s $_ if there are no arguments passed.