Substitute cc with c++ when compiling c++ test files for Siva Chandra : http://reviews.llvm.org/D6199

git-svn-id: https://llvm.org/svn/llvm-project/lldb/trunk@221692 91177308-0d34-0410-b5e6-96231b3b80d8
Add -std=c99 for building the test case of TestValueVarUpdate - for Siva Chandra : http://reviews.llvm.org/D6201

git-svn-id: https://llvm.org/svn/llvm-project/lldb/trunk@221694 91177308-0d34-0410-b5e6-96231b3b80d8