[analyzer] Add an integer version of the Circle tests in uninit-vals.m.

A floating-point version is nice for testing unknown values, but it's
good to be able to check all parts of the structure as well.

Test change only, no functionality change.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@177455 91177308-0d34-0410-b5e6-96231b3b80d8