hfsplus: incorrect return value

In case of memory allocation error, the return should be -ENOMEM, instead
of -ENOSPC.

Signed-off-by: Chengyu Song <csong84@gatech.edu>
Reviewed-by: Sergei Antonov <saproj@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>