drm/i915/display: take out dead code

if __waitfor timeout, ret will have -ETIMEDOUT. Then if condition
was met, and read_ret will have error that's handled.
Then if ret was zero, read_ret was zero ksv_ready must have value.

Signed-off-by: Juha-Pekka Heikkila <[e-mail]>
Reviewed-by: Jani Nikula <[e-mail]>
Signed-off-by: Mika Kahola <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]

drivers/gpu/drm/i915/display/intel_hdcp.c

···
 		return ret;
 	if (read_ret)
 		return read_ret;
-	if (!ksv_ready)
-		return -ETIMEDOUT;
 
 	return 0;
 }