Check for host validation before Create

[coveralls]

Pull Request Test Coverage Report for Build 9020607665

Details

• 4 of 4 (100.0%) changed or added relevant lines in 1 file are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage increased (+0.08%) to 65.251%

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Totals
Change from base Build 8993633325:	0.08%
Covered Lines:	4640
Relevant Lines:	7111

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💛 - Coveralls

[DanG100]

This can probably be deleted now:

https://github.com/openconfig/kne/blob/489aaeb632f8cf75d578a916ddaae55fb34e7d13/topo/node/node.go#L238

done

[alexmasi]

/gcbrun