Apply changes to clang-tidy (#662)

This allows some cpp features and disables llvmlibc specific rules

.clang-tidy

@@ -10,6 +10,7 @@ Checks:          '*,
     -cppcoreguidelines-pro-type-vararg,
     -cppcoreguidelines-special-member-functions,
     -fuchsia-default-arguments,
+    -fuchsia-default-arguments-calls,
     -fuchsia-statically-constructed-objects,
     -google-default-arguments,
     -google-explicit-constructor,
@@ -29,6 +30,7 @@ Checks:          '*,
     -hicpp-vararg,
     -llvm-header-guard,
     -llvm-include-order,
+    -llvmlibc-*,
     -misc-string-compare,
     -misc-unused-using-decls,
     -modernize-loop-convert,