attempt on such a system. The code tries mmap with /dev/zero and MIT-shm next.
Fix a possible filedesc leak, when the code tries to mmap shared memeory via
/dev/zero. Reuse the already open /dev/zero from a previous shmem_alloc call.
(same change; now without changing the indentation of the code)
git-svn-id: svn://svn.mplayerhq.hu/mplayer/trunk@1348 b3059339-0415-0410-9bf9-f77b7e298cf2