[MERGE][bug #165601] Fix typo limiting the offset coalescing

[Vincent Ladeuil]

>>>>> "john" == John Arbash Meinel <john at arbash-meinel.com> writes:

    john> John Arbash Meinel has voted approve.
    john> Status is now: Approved
    john> Comment:
    john> good catch.

    john> I still wonder about situations where we will get too many
    john> ranges, but this is definitely correct.

I will take them into account by issuing several GET ranged
requests in _readv and trying to get a better detection (if
possible*) of when we overflow the server, so that we can
distinguish between a server that can't handle mutiple ranges at
all and server which can handle some.

    Vincent

*: But I don't want to be too smart (and miss some unknown
 server) so I may just limit the size of the header with a
 reasonable default. If we want a huge number of ranges and
 collapsing them is not enough, chances are that we are dealing
 with a very big file and in that case issuing several requests
 (increasing latency cost) should be less important since we will
 download a lot of data anyway.