Consistently use neigh_ia label name.

[kormat]

This change is 

[karampok]

Reviewed 8 of 8 files at r1.
Reviewable status: all files reviewed, 1 unresolved discussion (waiting on @kormat)

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go/lib/prom/prom.go, line 37 at r1 (raw file):

	// LabelDst is the label for the destination.
	LabelDst = "dst"
	// LabelNeighIA is label for the neighbouring IA.

The IA should explain what stands for.

[karampok]

Reviewable status: all files reviewed, 1 unresolved discussion (waiting on @kormat)

[karampok]

Reviewed 1 of 1 files at r2.
Reviewable status: complete! all files reviewed, all discussions resolved