riscv: defconfig: Enable CONFIG_CLK_SOPHGO_CV1800

CONFIG_CLK_SOPHGO_CV1800 is required when booting the minimum
system for CV1800 series board.
Signed-off-by: Inochi Amaoto <inochiama@outlook.com>
Link: https://lore.kernel.org/r/IA1PR20MB49537E8B2D1FAAA7D5B8BDA2BB052@IA1PR20MB4953.namprd20.prod.outlook.comSigned-off-by: Palmer Dabbelt <palmer@rivosinc.com>

arch/riscv/configs/defconfig

@@ -233,6 +233,7 @@ CONFIG_VIRTIO_BALLOON=y
 CONFIG_VIRTIO_INPUT=y
 CONFIG_VIRTIO_MMIO=y
 CONFIG_RENESAS_OSTM=y
+CONFIG_CLK_SOPHGO_CV1800=y
 CONFIG_SUN8I_DE2_CCU=m
 CONFIG_SUN50I_IOMMU=y
 CONFIG_RPMSG_CHAR=y