Add support for arm64

Depends corresponding API change in kernel driver.

* Adds support for arm64
* Changes in the API between kernel driver and also secure world
  to make it 64-bit compatible while not requireing a 64bit secure
  world.
Cleanup loading of a TA

A TA is only loaded via tee-supplicant, directly supplying a
pointer to the TA binary is not supported any longer.
supplicant: simplify linked list implementation

* Simplifies linked list implementation by using queue.h macros
  instead.
* Fixes some theoretical memory leaks
Add Travis support

Signed-off-by: Pascal Brand <pascal.brand@st.com>