drm/ast: Fix calculation of MCLK

Some braces were missing causing an incorrect calculation.

Y.C. Chen from Aspeed provided me with the right formula
which I tested on AST2400 and 2500.

The MCLK isn't currently used by the driver (it will eventually
to filter modes) so the issue isn't catastrophic.

Also make the printed value a bit more meaningful
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Acked-by: Joel Stanley <joel@jms.id.au>
Tested-by: Y.C. Chen <yc_chen@aspeedtech.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>

drivers/gpu/drm/ast/ast_main.c

@@ -354,7 +354,7 @@ static int ast_get_dram_info(struct drm_device *dev)
 		div = 0x1;
 		break;
 	}
-	ast->mclk = ref_pll * (num + 2) / (denum + 2) * (div * 1000);
+	ast->mclk = ref_pll * (num + 2) / ((denum + 2) * (div * 1000));
 	return 0;
 }
 
@@ -498,7 +498,9 @@ int ast_driver_load(struct drm_device *dev, unsigned long flags)
 		if (ret)
 			goto out_free;
 		ast->vram_size = ast_get_vram_info(dev);
-		DRM_INFO("dram %d %d %d %08x\n", ast->mclk, ast->dram_type, ast->dram_bus_width, ast->vram_size);
+		DRM_INFO("dram MCLK=%u Mhz type=%d bus_width=%d size=%08x\n",
+			 ast->mclk, ast->dram_type,
+			 ast->dram_bus_width, ast->vram_size);
 	}
 
 	if (need_post)