postfix: add new recipe

Postfix is Wietse Venema's mail server that started life at IBM
research as an alternative to the widely-used Sendmail program.

Postfix attempts to be fast, easy to administer, and secure.
The outside has a definite Sendmail-ish flavor, but the inside
is completely different.

Signed-off-by: Jackie Huang <jackie.huang@windriver.com>
Signed-off-by: Joe MacDonald <joe_macdonald@mentor.com>
tnftp: add tnftp recipes file

Signed-off-by: Roy Li <rongqing.li@windriver.com>
Signed-off-by: Joe MacDonald <joe_macdonald@mentor.com>
Uprev tcpdump to 4.5.1

1. update the patch tcpdump_configure_no_-O2.patch
2. do not check libdlpi dependence on cross-compile, or else it will
cause do_qa_configure to fail.
3. do not check libpcap dependence, since the libpcap has been added
into DEPENDS, or else it will cause do_qa_configure to fail
4. make the check of getaddrinfo work on cross-compile

Signed-off-by: Roy Li <rongqing.li@windriver.com>
Signed-off-by: Joe MacDonald <joe_macdonald@mentor.com>