drm/radeon: force MSIs on RS690 asics

There are so many quirks, lets just try and force
this for all RS690s.  See:
https://bugs.freedesktop.org/show_bug.cgi?id=37679

Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org

drivers/gpu/drm/radeon/radeon_irq_kms.c

@@ -208,6 +208,10 @@ static bool radeon_msi_ok(struct radeon_device *rdev)
 	    (rdev->pdev->subsystem_device == 0x0185))
 		return true;
 
+	/* try and enable MSIs by default on all RS690s */
+	if (rdev->family == CHIP_RS690)
+		return true;
+
 	/* RV515 seems to have MSI issues where it loses
 	 * MSI rearms occasionally. This leads to lockups and freezes.
 	 * disable it by default.