ident.c: read /etc/mailname with strbuf_getline()
ident.c: read /etc/mailname with strbuf_getline()

Just in case /etc/mailname file was edited with a DOS editor,
read it with strbuf_getline() so that a stray CR is not included
as the last character of the mail hostname.

We _might_ want to more aggressively discard whitespace characters
around the line with strbuf_trim(), but that is a bit outside the
scope of this series.

Signed-off-by: Junio C Hamano <a6723cc3f76163bf7adb636a73ac3b0ceb3e6b9b@pobox.com>

destenson/git,destenson/git,destenson/git,destenson/git,destenson/git,destenson/git,destenson/git,destenson/git