compat: backport localizing the tty lock

compat: backport localizing the tty lock

Just undo make the lock generic for older kernels.
This backports:

commit d29f3ef39be4eec0362b985305fc526d9be318cf
Author: Alan Cox <alan@linux.intel.com>
Date:   Thu May 3 22:24:08 2012 +0100

    tty_lock: Localise the lock

    In each remaining case the tty_lock is associated with a specific tty. This
    means we can now lock on a per tty basis. We do need tty_lock_pair() for
    the pty case. Uglier but still a step in the right direction.

    [fixed up calls in 3 missing drivers - gregkh]

    Signed-off-by: Alan Cox <alan@linux.intel.com>
    Acked-by: Arnd Bergmann <arnd@arndb.de>
    Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
mcgrof@tux ~/compat (git::master)$ ckmake
Trying kernel                  3.4.0-030400rc1-generic	[OK]
Trying kernel                  3.3.0-030300rc2-generic	[OK]
Trying kernel                     3.2.2-030202-generic	[OK]
Trying kernel                    3.1.10-030110-generic	[OK]
Trying kernel                    3.0.18-030018-generic	[OK]
Trying kernel                  2.6.39-02063904-generic	[OK]
Trying kernel                  2.6.38-02063808-generic	[OK]
Trying kernel                  2.6.37-02063706-generic	[OK]
Trying kernel                  2.6.36-02063604-generic	[OK]
Trying kernel                  2.6.35-02063512-generic	[OK]
Trying kernel                  2.6.34-02063410-generic	[OK]
Trying kernel                  2.6.33-02063305-generic	[OK]
Trying kernel                  2.6.32-02063255-generic	[OK]
Trying kernel                  2.6.31-02063113-generic	[OK]
Trying kernel                  2.6.30-02063010-generic	[OK]
Trying kernel                  2.6.29-02062906-generic	[OK]
Trying kernel                  2.6.28-02062810-generic	[OK]
Trying kernel                    2.6.27-020627-generic	[OK]
Trying kernel                    2.6.26-020626-generic	[OK]
Trying kernel                    2.6.25-020625-generic	[OK]
Trying kernel                    2.6.24-020624-generic	[OK]

Signed-off-by: Luis R. Rodriguez <mcgrof@frijolero.org>