tee: export teedev_open() and teedev_close_context()

tee: export teedev_open() and teedev_close_context()

BugLink: https://bugs.launchpad.net/bugs/1963891
commit 1e2c3ef0496e72ba9001da5fd1b7ed56ccb30597 upstream.

Exports the two functions teedev_open() and teedev_close_context() in
order to make it easier to create a driver internal struct tee_context.

Reviewed-by: Sumit Garg <sumit.garg@linaro.org>
Signed-off-by: Jens Wiklander <jens.wiklander@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Paolo Pisati <paolo.pisati@canonical.com>