LU-11893 o2iblnd: add secondary IP address handling

LU-11893 o2iblnd: add secondary IP address handling

Using dev_get_by_name() in kiblnd_create_dev() means we can only
discover primary IP addresses. This breaks using network
aliasing which some people use. Move away from dev_get_by_name()
to using for_ifa() so we can detect any secondary IP addresses.

This patch is back-ported from the following one:
Lustre-commit: c4b39bf56bbcacd49d7f888a0745cd4b5580b36b
Lustre-change: https://review.whamcloud.com/34476

Change-Id: I03f2f8d18118b716a5eb5fb87694000ac06fe242
Signed-off-by: James Simmons <uja.ornl@yahoo.com>
Reviewed-by: Petros Koutoupis <pkoutoupis@cray.com>
Reviewed-by: Neil Brown <neilb@suse.com>
Reviewed-on: https://review.whamcloud.com/35248
Tested-by: Jenkins
Tested-by: Maloo <maloo@whamcloud.com>
Reviewed-by: Yang Sheng <ys@whamcloud.com>
Reviewed-by: Oleg Drokin <green@whamcloud.com>