riscv: rv32_defconfig: Update the defconfig

Update the rv32_defconfig:
 - Add 'CONFIG_DEVTMPFS_MOUNT=y' to match the RISC-V defconfig
 - Add CONFIG_HW_RANDOM=y and CONFIG_HW_RANDOM_VIRTIO=y to enable
   VirtIORNG when running on QEMU

Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
Signed-off-by: Paul Walmsley <paul.walmsley@sifive.com>

arch/riscv/configs/rv32_defconfig

@@ -34,6 +34,7 @@ CONFIG_PCIEPORTBUS=y
 CONFIG_PCI_HOST_GENERIC=y
 CONFIG_PCIE_XILINX=y
 CONFIG_DEVTMPFS=y
+CONFIG_DEVTMPFS_MOUNT=y
 CONFIG_BLK_DEV_LOOP=y
 CONFIG_VIRTIO_BLK=y
 CONFIG_BLK_DEV_SD=y
@@ -53,6 +54,8 @@ CONFIG_SERIAL_8250_CONSOLE=y
 CONFIG_SERIAL_OF_PLATFORM=y
 CONFIG_SERIAL_EARLYCON_RISCV_SBI=y
 CONFIG_HVC_RISCV_SBI=y
+CONFIG_HW_RANDOM=y
+CONFIG_HW_RANDOM_VIRTIO=y
 # CONFIG_PTP_1588_CLOCK is not set
 CONFIG_DRM=y
 CONFIG_DRM_RADEON=y