fs: Fix close_on_exec pointer in alloc_fdtable

fs: Fix close_on_exec pointer in alloc_fdtable

alloc_fdtable allocates space for the open_fds and close_on_exec
bitfields together, as 2 * nr / BITS_PER_BYTE.  close_on_exec needs to
point to open_fds + nr / BITS_PER_BYTE, not open_fds + nr /
BITS_PER_LONG, as introducted in 1fd36adc: Replace the fd_sets in
struct fdtable with an array of unsigned longs.

Signed-off-by: Bobby Powers <[email protected]>
Link: http://lkml.kernel.org/r/[email protected]
Acked-by: David Howells <[email protected]>
Signed-off-by: H. Peter Anvin <[email protected]>