Orangefs: add .lds files to .gitignore
orangefs: move bufmap related variables into struct pvfs2_bufmap

Besides keeping related variables together this allows initializing
it before making it public, and thus avoiding the need to nest
mmap_sem inside bufmap_init_sem.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Mike Marshall <hubcap@omnibond.com>