[tee] Add TEE Client API skeleton

The GlobalPlatform TEE Client API provides a communications API for
connecting Client Applications running in a rich execution environment
(in our case, Fuchsia) with an associated Trusted Application running
inside a Trusted Execution Environment (TEE).

This commit is limited to adding the constants, macros, data structures
and function stubs as defined by the TEE Client API specification. All
of the functions will return NOT_IMPLEMENTED for now.

Test: The library successfully builds, but no usages of it yet and its
behaviors are unimplemented.
Change-Id: I2ec9b925882592e98ac82a0d27ba104049f4639f