keymaster: Add keymaster implementation

Initial implementation of keymaster HAL APIs published in keymaster.h

Bug: 7106634
Change-Id: I1b1f611f1988212ce5f6f7f03b9a59ca652d92cf
Signed-off-by: Iliyan Malchev <malchev@google.com>
Merge tag 'android-4.2.2_r1.2' of https://android.googlesource.com/platform/hardware/qcom/keymaster into cm-10.1

Android 4.2.2 release 1.2

# gpg: Signature made Wed 17 Apr 2013 01:00:30 PM PDT using DSA key ID 9AB10E78
# gpg: Can't check signature: public key not found