Mark some tests as explicitly failing on clang/gcc as they pass on icc.
Also, rework the signed types test to check for signed or char type in the output as char is signed by default.


git-svn-id: https://llvm.org/svn/llvm-project/lldb/trunk@187533 91177308-0d34-0410-b5e6-96231b3b80d8