secure_element/aidl: Add error case for transmit()

Modify the semantics of transmit() to return a service
specific error with code CHANNEL_NOT_AVAILABLE if there
was an error in communicating with the secure element.

This can happen if the SE is put in low power mode when
no logical or basic channel is opened, e.g.

Bug: 270091254
Test: m VtsHalSecureElementTargetTest
Change-Id: I7df3ec6d9b6d5eeb2272971c44fc078a8558d2e6