LU-16822 tests: Update sanity-lnet router tests for IPv6

LU-16822 tests: Update sanity-lnet router tests for IPv6

Modify sanity-lnet test cases that test routing to work with IPv6
NIDs.

test_100/102/105/106:
  - Modified to use setup_router_test() to create a real router and
    use the associated LNet configuration in their tests.
test_101/103:
  - These test cases exercise the NID range functionality. They are
    skipped under IPv6 config

Test-Parameters: trivial testlist=sanity-lnet
Signed-off-by: Chris Horn <chris.horn@hpe.com>
Change-Id: I47b23e9c63d74d937cae7c7b8b1b27dd383fc0dc
Reviewed-on: https://review.whamcloud.com/c/fs/lustre-release/+/53728
Reviewed-by: James Simmons <jsimmons@infradead.org>
Reviewed-by: Frank Sehr <fsehr@whamcloud.com>
Reviewed-by: Oleg Drokin <green@whamcloud.com>
Tested-by: jenkins <devops@whamcloud.com>
Tested-by: Maloo <maloo@whamcloud.com>