xen: use lock-byte spinlock implementation
xen: use lock-byte spinlock implementation

Switch to using the lock-byte spinlock implementation, to avoid the
worst of the performance hit from ticket locks.

Signed-off-by: Jeremy Fitzhardinge <35cfe9f678a9e9bbdcf2f6e68cd105ce06d149b1@citrix.com>
Cc: Jens Axboe <cd8c6775e60d6f67a6984377324e5290df3d5358@kernel.dk>
Cc: Peter Zijlstra <645ca7d3a8d3d4f60557176cd361ea8351edc32b@chello.nl>
Cc: Christoph Lameter <a2610c5c148280bb6730402b12a8276c2f194fbe@linux-foundation.org>
Cc: Petr Tesarik <866189c2838db1556dc05eab495bc1ff82390cad@suse.cz>
Cc: Virtualization <65ac89e807f0ba8b231fca45370e2e73a1754d6e@lists.linux-foundation.org>
Cc: Xen devel <196a79ea1bad81d8c954adf793448b0a45442f28@lists.xensource.com>
Cc: Thomas Friebel <138acc96c6816a7a9c437d650395ee2d607c5ec2@amd.com>
Signed-off-by: Ingo Molnar <9dbbbf0688fedc85ad4da37637f1a64b8c718ee2@elte.hu>

KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs