drm/radeon: fix 64 bit divide in SI spm code

Forgot to use the appropriate math64 function.

Signed-off-by: Alex Deucher <[e-mail]>
Signed-off-by: Dave Airlie <[e-mail]>

drivers/gpu/drm/radeon/si_dpm.c

···
 	s64 temperature, t_slope, t_intercept, av, bv, t_ref;
 	s64 tmp;
 
-	i_leakage = drm_int2fixp(ileakage) / 100;
+	i_leakage = div64_s64(drm_int2fixp(ileakage), 100);
 	vddc = div64_s64(drm_int2fixp(v), 1000);
 	temperature = div64_s64(drm_int2fixp(t), 1000);