qdoc: Remove CR from command parameters

Although it is not recommended, it is allowed to have a carriage
return in a qdoc command parameter that is enclosed in curly
braces. qdoc is supposed to use QString::simplified() to sanitize the
string so that all whitespace is replaced by a single ' '. But in at
least one case, this didn't work, and the carriage return was left in
the string, which caused qdoc to report that it couldn't find links
that have the carriage return in them. The problem has been fixed by
replacing the carriage return with a ' ' right when and where it is
detected.

Change-Id: I31c31f19a1e4150b2e27613ecbac260c46a7109b
Task-number: QTBUG-42449
Reviewed-by: Topi Reiniö <topi.reinio@digia.com>

src/tools/qdoc/doc.cpp

@@ -2324,7 +2324,10 @@ QString DocParser::getBracedArgument(bool verbatim)
                 }
                 break;
             default:
-                arg += in[pos];
+                if (in[pos].isSpace() && !verbatim)
+                    arg += QChar(' ');
+                else
+                    arg += in[pos];
                 pos++;
             }
         }