drm/radeon: drop the mclk quirk for hainan

fixed by the new 58 mc firmware.
Acked-by: NEdward O'Callaghan <funfunctor@folklore1984.net>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/radeon/si_dpm.c

@@ -3016,7 +3016,6 @@ static void si_apply_state_adjust_rules(struct radeon_device *rdev,
 		    (rdev->pdev->device == 0x6665) ||
 		    (rdev->pdev->device == 0x6667)) {
 			max_sclk = 75000;
-			max_mclk = 80000;
 		}
 	}
 	/* Apply dpm quirks */