gpg: Fix searching for mail addresses in keyrings.
* g10/keyring.c (compare_name): Fix KEYDB_SEARCH_MODE_MAIL* searches in keyrings when the UID is a plain addr-spec.
Previously, 'gpg --list-key "<foo@example.org>"' failed if 1/ the
keyring format is used and 2/ the key's UID is a plain addr-spec
(cf. RFC2822 section 4.3), e.g. 'foo@example.org'.
- GnuPG-bug-id: T2930
- Signed-off-by: Justus Winter <justus@g10code.com>