Mateusz Piotrowski 82d0f865ee top: Sort flags in usage message
While here, fix the indentation of the second line in the message.

MFC after:	3 days
2021-11-18 15:56:47 +01:00
..
2021-11-18 15:56:47 +01:00
2021-11-18 15:56:47 +01:00