Qbs: Make pass on cpp.defines correctly to the C++ code model

When passing -DFOO to the compiler it will treat that as similar
to "#define FOO 1". Do the same when passing FOO on to the code
model.

Task-number: QTCREATORBUG-13384
Change-Id: I236d4731435e0559f75a3435dad9a8d935d42042
Reviewed-by: Orgad Shaneh <orgads@gmail.com>
Reviewed-by: Christian Kandeler <christian.kandeler@theqtcompany.com>

src/plugins/qbsprojectmanager/qbsproject.cpp

@@ -727,6 +727,8 @@ void QbsProject::updateCppCodeModel()
                 int pos = data.indexOf('=');
                 if (pos >= 0)
                     data[pos] = ' ';
+                else
+                    data.append(" 1"); // cpp.defines: [ "FOO" ] is considered to be "FOO=1"
                 grpDefines += (QByteArray("#define ") + data + '\n');
             }
             ppBuilder.setDefines(grpDefines);