[flang] Fix OPEN/WRITE(SIGN='SUPPRESS')

[klausler]

Summary

The keyword value was misspelled in the runtime.

flang/runtime/io-api.cpp

io.GetIoErrorHandler().SignalError(IostatErrorInKeyword,
         "Invalid ROUND='%.*s'", static_cast<int>(length), keyword);
     return false;
   }
 }
 
 bool IONAME(SetSign)(Cookie cookie, const char *keyword, std::size_t length) {
   IoStatementState &io{*cookie};
   ConnectionState &connection{io.GetConnectionState()};
-  static const char *keywords[]{"PLUS", "YES", "PROCESSOR_DEFINED", nullptr};
+  static const char *keywords[]{
+      "PLUS", "SUPPRESS", "PROCESSOR_DEFINED", nullptr};
   switch (IdentifyValue(keyword, length, keywords)) {
   case 0:
     connection.modes.editingFlags |= signPlus;
     return true;
   case 1:
   case 2: // processor default is SS
     connection.modes.editingFlags &= ~signPlus;
     return true;