Fix possible 'badarith' error for cover
Fix possible 'badarith' error for cover

Fix possible division by zero in case if a module doesn't export any
functions

jj1bdx/erlang.mk,crownedgrouse/erlang.mk,ingwinlu/erlang.mk,ninenines/erlang.mk,hairyhum/erlang.mk,nevar/erlang.mk,rabbitmq/erlang.mk