Revert "Merge branch 'mctp-i2c-driver'"

Revert "Merge branch 'mctp-i2c-driver'"

This reverts commit 71812af7234f30362b43ccff33f93890ae4c0655, reversing
changes made to cc0be1ad686fb29a4d127948486f40b17fb34b50.

Wolfram Sang says:

Please revert. Besides the driver in net, it modifies the I2C core
code. This has not been acked by the I2C maintainer (in this case me).
So, please don't pull this in via the net tree. The question raised here
(extending SMBus calls to 255 byte) is complicated because we need ABI
backwards compatibility.

Link: https://lore.kernel.org/all/YZJ9H4eM%2FM7OXVN0@shikoro/
Signed-off-by: Jakub Kicinski <kuba@kernel.org>