cmd/compile/internal/types2: superfluous error message for [...]byte("foo")

[griesemer]

package p
var _ = [...]byte("foo")

produces the type checker errors:

x.go:2:9: invalid use of [...] array (outside a composite literal)
x.go:2:19: cannot convert "foo" (untyped string constant) to [-1]byte

The 2nd error is not needed and also misleading.

cc: @findleyr

[griesemer]

Correction: go/types seems to be doing it right.

x.go:2:10: expected array length, found '...'