drcov -dump_text table count is sometimes wrong

See https://groups.google.com/d/msgid/dynamorio-users/f9a1c229-4284-483f-8da7-79d120e6d330n%40googlegroups.com?utm_medium=email&utm_source=footer

There appears to be a format string error with a 32-bit output type for a 64-bit entry count for -dump_text: https://github.com/DynamoRIO/dynamorio/blob/master/ext/drcovlib/drcovlib.c#L142 This would not affect binary output.