drm: etnaviv: Replace of_platform.h with explicit includes

Etnaviv doesn't use anything from of_platform.h, but depends on
of.h, of_device.h, and platform_device.h which are all implicitly
included, but that is going to be removed soon.
Signed-off-by: Rob Herring <robh@kernel.org>
Tested-by: Sui Jingfeng <suijingfeng@loongson.cn>
Signed-off-by: Lucas Stach <l.stach@pengutronix.de>

drivers/gpu/drm/etnaviv/etnaviv_drv.c

@@ -6,7 +6,9 @@
 #include <linux/component.h>
 #include <linux/dma-mapping.h>
 #include <linux/module.h>
-#include <linux/of_platform.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/platform_device.h>
 #include <linux/uaccess.h>
 
 #include <drm/drm_debugfs.h>