remoteproc/mediatek: fix null pointer dereference on null scp pointer

Currently when pointer scp is null a dev_err is being called that
references the pointer which is the very thing we are trying to
avoid doing. Remove the extraneous error message to avoid this
issue.

Addresses-Coverity: ("Dereference after null check")
Fixes: 63c13d61 ("remoteproc/mediatek: add SCP support for mt8183")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Link: https://lore.kernel.org/r/20200918152428.27258-1-colin.king@canonical.comSigned-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>

drivers/remoteproc/mtk_scp_ipi.c

@@ -30,10 +30,8 @@ int scp_ipi_register(struct mtk_scp *scp,
 		     scp_ipi_handler_t handler,
 		     void *priv)
 {
-	if (!scp) {
-		dev_err(scp->dev, "scp device is not ready\n");
+	if (!scp)
 		return -EPROBE_DEFER;
-	}
 
 	if (WARN_ON(id >= SCP_IPI_MAX) || WARN_ON(handler == NULL))
 		return -EINVAL;