Add ssh dump support
changes including below items:
1. sshkey option
2. sshkey propagate
3. fix a bug of _server ip calculation for dump target string
4. change the prefix of kdump hook from 93 to 01 to avoid dhclient and
other cleanups happening before us
5. enable network with dracut cmdline rd.neednet=1 when there's network
target config
[v1 - v2]:
Only check_ssh_target when there's ssh dump target in kdump config file
[v2 -> v3]
style fixes: trailing spaces and space before tab indent
remove set -x
simply check_ssh_target
use awk to get sshkey option value
change pivot hook order to 0000
Signed-off-by: Dave Young <dyoung@redhat.com>