improve readability in handleQueryP2P

[fedekunze]

handleQueryP2P this should use the inverse conditional for improved readability:

if len(path) < 4 {
        msg := "path should be p2p filter <addr|id> <parameter>"
	return sdk.ErrUnknownRequest(msg).QueryResult()
}

...

Originally posted by @fedekunze in #4748

[github-actions]

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