fix f_count description in Documentation/filesystems/files.txt
Eric Dumazet authored

Documentation/filesystems/files.txt was not updated when
f_count became an atomic_long_t.
atomic_long_inc_not_zero() is now used instead of atomic_inc_not_zero()
Signed-off-by: default avatarAl Viro <viro@zeniv.linux.org.uk>
fd659fd6