[dev.regabi] cmd/compile: fix linux-amd64-noopt builder

CL 284223 tightened down the allowed expressions in mayCall, but
evidently a little too tight. The linux-amd64-noopt builder does in
fact see expressions with non-empty Init lists in arguments list.

Since I believe these can only appear on the RHS of LogicalExpr
expressions, this CL relaxes that one case.

Change-Id: I1e6bbd0449778c40ed2610b3e1ef6a825a84ada7
Reviewed-on: https://go-review.googlesource.com/c/go/+/284226


Trust: Matthew Dempsky <mdempsky@google.com>
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Cuong Manh Le <cuong.manhle.vn@gmail.com>