host_integerp vs [] decls

[DJ Delorie]

> Didn't we decide that "invalid" was preferred to "illegal"?

Neither ended up in the docs.  The new wording is this:

  Non-empty initialization of zero-length arrays is now treated like
  any case where there are more initializer elements than the array
  holds, in that a suitable warning about "excess elements in array"
  is given, and the excess elements (all of them, in this case) are
  ignored.