libteec: Fix the initial value of shm->id in teec_pre_process_operation()

teec_pre_process_operation() returns the error code of
teec_pre_process_tmpref() directly when it failed
(such as allocate a very large size of SHM).
In this situation, the shm->id is still zero.
It results in the wrong error handling.
When TEEC_ReleaseSharedMemory() is called in function
teec_free_temp_refs(), it would close a wrong fd 0
since the shm->id is not -1 (the initial value is zero).

Reviewed-by: Jens Wiklander <jens.wiklander@linaro.org>
Reviewed-by: Jerome Forissier <jerome@forissier.org>
Signed-off-by: YJ Chiang <yj.chiang@mediatek.com>
Signed-off-by: Rayan Hu <Rayan.Hu@mediatek.com>
Signed-off-by: JY Ho <JY.Ho@mediatek.com>