cmd/tests: Don't convert lines with DOS endings in convert_input_data.

programs/cmd/tests/batch.c

@@ -47,6 +47,7 @@ static const char* convert_input_data(const char *data, DWORD size, DWORD *new_s
     for (i = 0; i < size; i++) {
         switch (data[i]) {
             case '\n':
+                if (data[i-1] != '\r')
                     *ptr++ = '\r';
                 *ptr++ = '\n';
                 break;