drm/vc4: crtc: Turn static const variable into a define

The hvs_latency_pix variable doesn't need to be a variable and can just be
defined.
Reviewed-by: Eric Anholt <eric@anholt.net>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://patchwork.freedesktop.org/patch/msgid/8535c679f79af8abaa1b7796261bfeda11f874fd.1590594512.git-series.maxime@cerno.tech

drivers/gpu/drm/vc4/vc4_crtc.c

@@ -44,6 +44,8 @@
 #include "vc4_drv.h"
 #include "vc4_regs.h"
 
+#define HVS_FIFO_LATENCY_PIX	6
+
 #define CRTC_WRITE(offset, val) writel(val, vc4_crtc->regs + (offset))
 #define CRTC_READ(offset) readl(vc4_crtc->regs + (offset))
 
@@ -231,18 +233,17 @@ vc4_crtc_update_gamma_lut(struct drm_crtc *crtc)
 static u32 vc4_get_fifo_full_level(u32 format)
 {
 	static const u32 fifo_len_bytes = 64;
-	static const u32 hvs_latency_pix = 6;
 
 	switch (format) {
 	case PV_CONTROL_FORMAT_DSIV_16:
 	case PV_CONTROL_FORMAT_DSIC_16:
-		return fifo_len_bytes - 2 * hvs_latency_pix;
+		return fifo_len_bytes - 2 * HVS_FIFO_LATENCY_PIX;
 	case PV_CONTROL_FORMAT_DSIV_18:
 		return fifo_len_bytes - 14;
 	case PV_CONTROL_FORMAT_24:
 	case PV_CONTROL_FORMAT_DSIV_24:
 	default:
-		return fifo_len_bytes - 3 * hvs_latency_pix;
+		return fifo_len_bytes - 3 * HVS_FIFO_LATENCY_PIX;
 	}
 }