Merge changes from topic "refactor-mb" into integration

* changes:
  docs(measured boot): add measured boot platform functions
  refactor(measured boot): make measurement strings compliant with SBSG
  feat(plat/fvp): pass Event Log addr and size from BL1 to BL2
  feat(measured_boot): update tb_fw_config with event log properties
  feat(measured_boot): image hash measurement and recording in BL1
  refactor(measured boot): remove platform calls from Event Log driver
  refactor(measured_boot): remove passing of BL2 hash via device tree
  refactor(measured boot): move BL2 measurement to platform layer
  refactor(measured boot): rename add_event2()
  refactor(measured boot): move image measurement to generic layer
  build(measured boot): rename measured boot makefile
  feat(measured boot): move init and teardown functions to platform layer
  refactor(measured boot): rename tpm_record_measurement()