Update the Trusty Keymaster directory structure

Added three new directories:
  - include: contains ipc and legacy header files
  - ipc: contains common keymaster IPC code that can be shared between HALS
  - legacy: contains the old style HAL implementation

Test: trusty_keymaster_tipc & keystore.trusty compile
Bug:110153632
Change-Id: I2fdaa9d3d0421a0e359c05807ab5f0a12c5d3996