drm/nouveau/i2c: resume use of i2c-algo-bit, rather than custom stack

Previous issues with i2c-algo-bit have now been resolved.

This is a revert of f553b79c03f0dbd52f6f03abe8233a2bef8cbd0d mostly,
due to fixes in the i2c core repairing the original issue, this code
isn't required and was causing regressions.

Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
Reported-by: Nick Bowler <nbowler@elliptictech.com>
Tested-by: Nick Bowler <nbowler@elliptictech.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
diff --git a/drivers/gpu/drm/nouveau/nouveau_i2c.h b/drivers/gpu/drm/nouveau/nouveau_i2c.h
index 4d2e4e9..1d08389 100644
--- a/drivers/gpu/drm/nouveau/nouveau_i2c.h
+++ b/drivers/gpu/drm/nouveau/nouveau_i2c.h
@@ -34,6 +34,7 @@
 struct nouveau_i2c_chan {
 	struct i2c_adapter adapter;
 	struct drm_device *dev;
+	struct i2c_algo_bit_data bit;
 	struct list_head head;
 	u8  index;
 	u8  type;