Fix possible segv in the gpgme_op_card_edit.
Fix possible segv in the gpgme_op_card_edit.

* src/edit.c (gpgme_op_edit_start, gpgme_op_card_edit_start): Do not
deref a NULL KEY in TRACE_BEG.

gpg/gpgme,gpg/gpgme,gpg/gpgme,gpg/gpgme,gpg/gpgme,gpg/gpgme,gpg/gpgme