Use fuzzy comparison for another Flickable StopAtBounds case.

Be consistent with 268f4615dcf19aad3603833af83ba28eca886aa5, and use
fuzzyLessThanOrEqualTo when checking whether we are at or past the bounds
when dragging. This prevents a condition where:

1. A Flickable with StopAtBounds is at one of the bounds.
2. A quick flick will sometimes (rarely) cause the Flickable to flick
   past the bounds.

Change-Id: I4165fa133f556fb9d47cc691d11b2ecb77746b33
Reviewed-by: Martin Jones <martin.jones@jollamobile.com>