qemu: riscv: Enable UFS support

This enables UFS support for QEMU RISC-V 'virt' machine.

Signed-off-by: Bin Meng <bmeng@tinylab.org>
Reviewed-by: Neha Malcom Francis <n-francis@ti.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
diff --git a/board/emulation/qemu-riscv/Kconfig b/board/emulation/qemu-riscv/Kconfig
index d56b4b5..f3ee1f6 100644
--- a/board/emulation/qemu-riscv/Kconfig
+++ b/board/emulation/qemu-riscv/Kconfig
@@ -82,5 +82,7 @@
 	imply USB_XHCI_PCI
 	imply USB_KEYBOARD
 	imply CMD_USB
+	imply UFS
+	imply UFS_PCI
 
 endif
diff --git a/doc/board/emulation/qemu-riscv.rst b/doc/board/emulation/qemu-riscv.rst
index 61137bc..8a5eb1e 100644
--- a/doc/board/emulation/qemu-riscv.rst
+++ b/doc/board/emulation/qemu-riscv.rst
@@ -131,7 +131,13 @@
     -drive if=none,file=riscv64.img,format=raw,id=mydisk \
     -device ide-hd,drive=mydisk,bus=ahci.0
 
-You will have to run 'scsi scan' to use it.
+or alternatively attach an emulated UFS::
+
+    -device ufs,id=ufs0 \
+    -drive if=none,file=test.img,format=raw,id=lun0 \
+    -device ufs-lu,drive=lun0,bus=ufs0
+
+You will have to run 'scsi scan' to use them.
 
 A video console can be emulated in RISC-V virt machine by removing "-nographic"
 and adding::