Merge tag 'tee-drv-dynamic-shm+fixes-for-v4.16' of https://git.linaro.org/people/jens.wiklander/linux-tee into next/drivers

This pull request updates the previous tee-drv-dynamic-shm-for-v4.16 pull
request with five new patches fixing review comments and errors.

Apart from three small fixes there's two larger patches that in the end
checks that memory to be registered really is normal cached memory.

* tag 'tee-drv-dynamic-shm+fixes-for-v4.16' of https://git.linaro.org/people/jens.wiklander/linux-tee:
  tee: shm: Potential NULL dereference calling tee_shm_register()
  tee: shm: don't put_page on null shm->pages
  tee: shm: make function __tee_shm_alloc static
  tee: optee: check type of registered shared memory
  tee: add start argument to shm_register callback

Signed-off-by: Olof Johansson <olof@lixom.net>