Add missing include for llvm::Error after 74ec038

Author: slackito

llvm/include/llvm/Frontend/OpenMP/OMPIRBuilder.h

@@ -22,6 +22,7 @@
 #include "llvm/IR/Module.h"
 #include "llvm/IR/ValueMap.h"
 #include "llvm/Support/Allocator.h"
+#include "llvm/Support/Error.h"
 #include "llvm/TargetParser/Triple.h"
 #include <forward_list>
 #include <map>