"-serial mon:stdio" was already injected elsewhere, so remove
duplication. That argument, when coming from the common infrastructure,
also comes as one of the last ones. Because of that, the former "-serial
vc" was taking precedence and we were never seeing output on stdio.
Removing the virtual console altogether, for now, fixes that.
Finally, since cmake came in, we have to fix the path for the fsdev
argument to QEMU as well.
Signed-off-by: Gustavo Lima Chaves <gustavo.lima.chaves@intel.com>