[ubsan] Pass a set of checks to skip to EmitTypeCheck() (NFC)

CodeGenFunction::EmitTypeCheck accepts a bool flag which controls
whether or not null checks are emitted. Make this a bit more flexible by
changing the bool to a SanitizerSet.

Needed for an upcoming change which deals with a scenario in which we
only want to emit null checks.

llvm-svn: 295514
diff --git a/clang/lib/CodeGen/CodeGenFunction.h b/clang/lib/CodeGen/CodeGenFunction.h
index b830df7..09f1763 100644
--- a/clang/lib/CodeGen/CodeGenFunction.h
+++ b/clang/lib/CodeGen/CodeGenFunction.h
@@ -2252,7 +2252,7 @@
   /// appropriate size and alignment for an object of type \p Type.
   void EmitTypeCheck(TypeCheckKind TCK, SourceLocation Loc, llvm::Value *V,
                      QualType Type, CharUnits Alignment = CharUnits::Zero(),
-                     bool SkipNullCheck = false);
+                     SanitizerSet SkippedChecks = SanitizerSet());
 
   /// \brief Emit a check that \p Base points into an array object, which
   /// we can access at index \p Index. \p Accessed should be \c false if we