Revert "get rid of unnecessary warning"

This reverts commit e5321437.

OpCode 0 (ocPush) was deliberately included in the assertion as it is
never a mapping to a function or operator name.

formula/source/core/api/FormulaCompiler.cxx

@@ -488,8 +488,8 @@ uno::Sequence< sheet::FormulaOpCodeMapEntry > FormulaCompiler::OpCodeMap::create
 
 void FormulaCompiler::OpCodeMap::putOpCode( const String & rStr, const OpCode eOp )
 {
-    DBG_ASSERT( sal_uInt16(eOp) < mnSymbols, "OpCodeMap::putOpCode: OpCode out of range");
-    if (sal_uInt16(eOp) < mnSymbols)
+    DBG_ASSERT( 0 < eOp && sal_uInt16(eOp) < mnSymbols, "OpCodeMap::putOpCode: OpCode out of range");
+    if (0 < eOp && sal_uInt16(eOp) < mnSymbols)
     {
         DBG_ASSERT( (mpTable[eOp].Len() == 0) || (mpTable[eOp] == rStr) ||
             (eOp == ocCurrency) || (eOp == ocSep) || (eOp == ocArrayColSep) ||