It eases code review, unit is explicit.

Patch generated using:

  $ git grep -n '[<>][<>]= ?[1-5]0'

and modified manually.

Suggested-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-Id: <20180625124238.25339-45-f4bug@amsat.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>