Since all AEAD ciphers now go through EVP_AEAD interface, the code which
uses EVP_Cipher interface no longer needs any of AEAD handling logic.
This also removes EVP_CTRL_AEAD_TLS1_AAD from GCM interface, which was
duplicating non-TLS-specific GCM logic and is not used anymore.
Change-Id: I5ddae880e7bc921337f9149a0acfdd00c9a478c3
Initial fork from f2d678e6e89b6508147086610e985d4e8416e867 (1.0.2 beta).
(This change contains substantial changes from the original and
effectively starts a new history.)
