drm/tegra: dc: Use unsigned int for register offsets

Register offsets are usually fairly small numbers, so an unsigned int is
more than enough to represent them.
Signed-off-by: Thierry Reding <treding@nvidia.com>

drivers/gpu/drm/tegra/drm.h

@@ -172,12 +172,12 @@ static inline struct tegra_dc *to_tegra_dc(struct drm_crtc *crtc)
 }
 
 static inline void tegra_dc_writel(struct tegra_dc *dc, u32 value,
-				   unsigned long offset)
+				   unsigned int offset)
 {
 	writel(value, dc->regs + (offset << 2));
 }
 
-static inline u32 tegra_dc_readl(struct tegra_dc *dc, unsigned long offset)
+static inline u32 tegra_dc_readl(struct tegra_dc *dc, unsigned int offset)
 {
 	return readl(dc->regs + (offset << 2));
 }