[SRU[[Trusty] Synaptics HID touchpad driver

[AceLan Kao]

SRU JUSTIFICATION

BugLink: https://bugs.launchpad.net/bugs/1305522

IMPACT: The Synaptics touchpad with i2c interface doesn't work well
after kernel starting supporting i2c-hid device. And the solution
currently we provided is to blacklist i2c_hid driver and let the
touchpad fallback to use PS/2 interface.

FIX: I cherry-picked the Synaptics i2c driver from
git://git.kernel.org/pub/scm/linux/kernel/git/jikos/hid.git for-next
Now all commits are going into linus' tree.

TEST: I built a test kernel and post it on launchpad for users to test
it for almost a month. It works well on my Dell laptop and it doesn't
affect touchscreen now.
   http://people.canonical.com/~acelan/bugs/lp1305522/20140523/

git://kernel.ubuntu.com/acelan/ubuntu-trusty.git rmi4