drm/sun4i: Allow building the driver on RISC-V

Allwinner D1 is a RISC-V SoC which contains a DE 2.0 engine. Let's
remove the dependency on a specific CPU architecture, so the driver can
be built wherever ARCH_SUNXI is selected.
Acked-by: Jernej Skrabec <jernej.skrabec@gmail.com>
Signed-off-by: Samuel Holland <samuel@sholland.org>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://patchwork.freedesktop.org/patch/msgid/20220424162633.12369-6-samuel@sholland.org

drivers/gpu/drm/sun4i/Kconfig

 # SPDX-License-Identifier: GPL-2.0-only
 config DRM_SUN4I
 	tristate "DRM Support for Allwinner A10 Display Engine"
-	depends on DRM && (ARM || ARM64) && COMMON_CLK
+	depends on DRM && COMMON_CLK
 	depends on ARCH_SUNXI || COMPILE_TEST
 	select DRM_GEM_CMA_HELPER
 	select DRM_KMS_HELPER