drm/omap: Allow build with COMPILE_TEST=y

Allow omapdrm to be built with COMPILE_TEST=y for greater
coverage. Builds fine on x86/x86_64 at least.

Cc: Tomi Valkeinen <tomi.valkeinen@ideasonboard.com>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240408170426.9285-16-ville.syrjala@linux.intel.comReviewed-by: Tomi Valkeinen <tomi.valkeinen@ideasonboard.com>

drivers/gpu/drm/omapdrm/Kconfig

@@ -2,7 +2,7 @@
 config DRM_OMAP
 	tristate "OMAP DRM"
 	depends on DRM && OF
-	depends on ARCH_OMAP2PLUS
+	depends on ARCH_OMAP2PLUS || COMPILE_TEST
 	select DRM_KMS_HELPER
 	select FB_DMAMEM_HELPERS_DEFERRED if DRM_FBDEV_EMULATION
 	select VIDEOMODE_HELPERS