optee-client: Add daemon and library for OP-TEE

Linux daemon (tee-supplicant) and library (libteec) for
using trusted applications (TA's) of OP-TEE secure OS.

This code comes from linaro repository:
https://git.linaro.org/openembedded/meta-linaro.git/tree/meta-optee



Signed-off-by: Santeri Salko <santeri.salko@huawei.com>