configs/qemu-ppc-virtex-ml507: remove stray qemu-system entries

Removed unused config entries that sneaked in from commit
a8956b2b53cad04ddcb56f3d3e2dcf8f6051c77a

Signed-off-by: Gustavo Zacarias <gustavo@zacarias.com.ar>
Reviewed-by: "Yann E. MORIN" <yann.morin.1998@free.fr>
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>

configs/qemu_ppc_virtex_ml507_defconfig

@@ -22,8 +22,3 @@ BR2_LINUX_KERNEL_DEFCONFIG="44x/virtex5"
 BR2_LINUX_KERNEL_VMLINUX=y
 BR2_LINUX_KERNEL_DTS_SUPPORT=y
 BR2_LINUX_KERNEL_INTREE_DTS_NAME="virtex440-ml507"
-
-# Qemu
-BR2_PACKAGE_HOST_QEMU_SYSTEM=y
-BR2_PACKAGE_HOST_QEMU_SYSTEM_VERSION="2.1.2"
-BR2_PACKAGE_HOST_QEMU_SYSTEM_ARGS="-M virtex-ml507 -kernel output/images/vmlinux -m 256 -append 'console=ttyS0' -display none -nographic -dtb output/images/virtex440-ml507.dtb"