gpg: Use a more descriptive prompt for symmetric decryption.
* g10/keydb.h (GETPASSWORD_FLAG_SYMDECRYPT): New. (passphrase_to_dek_ext): Remove this obsolete prototype. * g10/passphrase.c (passphrase_get): Add arg flags. Use new flag value. (passphrase_to_dek): Add arg flags and pass it on. * g10/mainproc.c (proc_symkey_enc): Use new flag.
- Signed-off-by: Werner Koch <wk@gnupg.org>