Go ahead and make this write unconditional. Making it conditional is more work

in both the append and non-append modes.  Also, always truncating the partial
write makes the behavior of the function more consistent, where in any type of
write, no partial result is left in the buffer.

Thanks for the feedback, luigi


git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@48109 65c4cc65-6c06-0410-ace0-fbb531ad65f3