drm/radeon/dpm: Reenabling SS on Cayman

It reverts commit c745fe611ca42295c9d91d8e305d27983e9132ef now that
Cayman is stable since VDDCI fix. Spread spectrum was not the culprit.

This depends on b0880e87c1fd038b84498944f52e52c3e86ebe59
(drm/radeon/dpm: fix vddci setup typo on cayman).

Signed-off-by: Alexandre Demers <alexandre.f.demers@gmail.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org

drivers/gpu/drm/radeon/rv770_dpm.c

@@ -2329,12 +2329,6 @@ void rv770_get_engine_memory_ss(struct radeon_device *rdev)
 	pi->mclk_ss = radeon_atombios_get_asic_ss_info(rdev, &ss,
 						       ASIC_INTERNAL_MEMORY_SS, 0);
 
-	/* disable ss, causes hangs on some cayman boards */
-	if (rdev->family == CHIP_CAYMAN) {
-		pi->sclk_ss = false;
-		pi->mclk_ss = false;
-	}
-
 	if (pi->sclk_ss || pi->mclk_ss)
 		pi->dynamic_ss = true;
 	else