BACKPORT: tee: optee: check type of registered shared memory

Checks the memory type of the pages to be registered as shared memory.
Only normal cached memory is allowed.

Change-Id: I319740ef448e7d7ce31efd2b5456972da192fce3
Signed-off-by: Jens Wiklander <jens.wiklander@linaro.org>
(cherry picked from commit cdbcf83d29c1bf2aaa65260e74beaac1bcdc231c)
Signed-off-by: Victor Chong <victor.chong@linaro.org>