Caught a last-minute issue with my small-int ops

I apparently missed a paragraph about math only being supported on
32- and 64-bit ints.  Oops.



git-svn-id: http://svn.code.sf.net/p/chapel/code/trunk@22084 3a8e244f-b0f2-452b-bcba-4c88e055c3ca
Spec for the release



git-svn-id: http://svn.code.sf.net/p/chapel/code/trunk@22085 3a8e244f-b0f2-452b-bcba-4c88e055c3ca