Silence some -Wstring-conversion warnings

lldbassert(!"foo") -> lldbassert(0 && "foo")

In one case, this actually detected a logic error in the assertion (missing !).

llvm-svn: 291102
diff --git a/lldb/source/Symbol/ClangASTContext.cpp b/lldb/source/Symbol/ClangASTContext.cpp
index caebd0c..e5fb9dc 100644
--- a/lldb/source/Symbol/ClangASTContext.cpp
+++ b/lldb/source/Symbol/ClangASTContext.cpp
@@ -2119,7 +2119,7 @@
   if (!type_name.IsEmpty() &&
       (type = GetTypeForIdentifier<clang::CXXRecordDecl>(type_name))
           .IsValid()) {
-    lldbassert("Trying to create a type for an existing name");
+    lldbassert(0 && "Trying to create a type for an existing name");
     return type;
   }