Revert "media: cec: core: add adap_nb_transmit_canceled() callback"

This reverts commit d6610151 which is
commit da53c36d upstream.

It breaks the Android ABI and is not needed for Android systems at this
point in time.  If needed in the future, it can come back in an abi-safe
way.

Bug: 161946584
Change-Id: I65b4767764af29e74b2e349e7943f4f70f333823
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>