MIPS: Add board config for virt board

Aligned with QEMU MIPS virt board.
Signed-off-by: Jiaxun Yang <jiaxun.yang@flygoat.com>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

arch/mips/configs/generic/board-virt.config

+CONFIG_COMMON_CLK=y
+
+CONFIG_GOLDFISH=y
+CONFIG_GOLDFISH_PIC=y
+
+CONFIG_PCI=y
+CONFIG_PCI_MSI=y
+CONFIG_PCI_HOST_GENERIC=y
+
+CONFIG_POWER_RESET=y
+CONFIG_POWER_RESET_SYSCON=y
+CONFIG_POWER_RESET_SYSCON_POWEROFF=y
+CONFIG_SYSCON_REBOOT_MODE=y
+
+CONFIG_RTC_CLASS=y
+CONFIG_RTC_DRV_GOLDFISH=y
+
+CONFIG_SERIAL_8250=y
+CONFIG_SERIAL_8250_CONSOLE=y
+CONFIG_SERIAL_OF_PLATFORM=y
+
+CONFIG_MTD=y
+CONFIG_MTD_CFI=y
+
+CONFIG_USB=y
+CONFIG_USB_EHCI_HCD=y
+CONFIG_USB_OHCI_HCD=y
+CONFIG_USB_XHCI_HCD=y
+
+CONFIG_VIRTIO_CONSOLE=y
+CONFIG_VIRTIO_PCI=y
+CONFIG_VIRTIO_MMIO=y
+CONFIG_VIRTIO_MMIO_CMDLINE_DEVICES=y
+CONFIG_VIRTIO_BALLOON=y
+CONFIG_VIRTIO_BLK=y
+CONFIG_VIRTIO_NET=y
+CONFIG_NET_9P=y
+CONFIG_NET_9P_VIRTIO=y