minion.Matcher.pillar_exact_match: fix utils.subdict_match() call

************* Module salt.minion
salt/minion.py:2492: [E1123(unexpected-keyword-arg), Matcher.pillar_exact_match] Unexpected keyword argument 'delim' in function call
Merge pull request #17710 from hulu/delim

minion.Matcher.pillar_exact_match: fix utils.subdict_match() call