Commit 371f0f085f ("ARM: 8426/1: dma-mapping: add missing range check
in dma_mmap()") introduced offset-checking for mappings, which collides
with the fake-offset the drm sets for gems.
Other drm-drivers set this offset to 0 before doing the mapping, so
this looks like the correct way to go for rockchip as well.
Fixes: 371f0f085f ("ARM: 8426/1: dma-mapping: add missing range check in dma_mmap()")
Signed-off-by: Heiko Stuebner <heiko@sntech.de>