drm/tegra: dc: Registers are 32 bits wide

Using an unsigned long type will cause these variables to become 64-bit
on 64-bit SoCs. In practice this should always work, but there's no need
for carrying around the additional 32 bits.
Signed-off-by: Thierry Reding <treding@nvidia.com>

drivers/gpu/drm/tegra/dc.c

@@ -1005,7 +1005,7 @@ static int tegra_dc_show_regs(struct seq_file *s, void *data)
 	struct tegra_dc *dc = node->info_ent->data;
 
 #define DUMP_REG(name)						\
-	seq_printf(s, "%-40s %#05x %08lx\n", #name, name,	\
+	seq_printf(s, "%-40s %#05x %08x\n", #name, name,	\
 		   tegra_dc_readl(dc, name))
 
 	DUMP_REG(DC_CMD_GENERAL_INCR_SYNCPT);

drivers/gpu/drm/tegra/drm.h

@@ -139,16 +139,15 @@ static inline struct tegra_dc *to_tegra_dc(struct drm_crtc *crtc)
 	return crtc ? container_of(crtc, struct tegra_dc, base) : NULL;
 }
 
-static inline void tegra_dc_writel(struct tegra_dc *dc, unsigned long value,
-				   unsigned long reg)
+static inline void tegra_dc_writel(struct tegra_dc *dc, u32 value,
+				   unsigned long offset)
 {
-	writel(value, dc->regs + (reg << 2));
+	writel(value, dc->regs + (offset << 2));
 }
 
-static inline unsigned long tegra_dc_readl(struct tegra_dc *dc,
-					   unsigned long reg)
+static inline u32 tegra_dc_readl(struct tegra_dc *dc, unsigned long offset)
 {
-	return readl(dc->regs + (reg << 2));
+	return readl(dc->regs + (offset << 2));
 }
 
 struct tegra_dc_window {