message: build: make clean removes .gcda and .gcno files from fuzz directory
  With this commit, make clean now removes coverage files from the
  fuzzing directory. Without this, subsequent fuzzing runs would have
  garbled coverage signals for files in the fuzz directory as
  they were never deleted with make clean.
diff: @@ -1200,7 +1200,7 @@ nodist_test_test_peercoin_SOURCES = $(GENERATED_TEST_FILES)
  $(BITCOIN_TESTS): $(GENERATED_TEST_FILES)
  -CLEAN_BITCOIN_TEST = test/*.gcda test/*.gcno $(GENERATED_TEST_FILES) $(BITCOIN_TESTS:=.log)
  +CLEAN_BITCOIN_TEST = test/*.gcda test/*.gcno test/fuzz/*.gcda test/fuzz/*.gcno $(GENERATED_TEST_FILES) $(BITCOIN_TESTS:=.log)
  CLEANFILES += $(CLEAN_BITCOIN_TEST)
  