[media] drivers/media/pci: use memmove for overlapping regions

Change several memcpy() to memmove() in cases when the regions are
definitely overlapping; memcpy() of overlapping regions is undefined
behavior in C and can produce different results depending on the compiler,
the memcpy implementation, etc.

Cc: Andy Walls <awalls@md.metrocast.net>
Signed-off-by: Nickolai Zeldovich <nickolai@csail.mit.edu>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

drivers/media/pci/bt8xx/dst_ca.c

@@ -180,11 +180,11 @@ static int ca_get_app_info(struct dst_state *state)
 	put_command_and_length(&state->messages[0], CA_APP_INFO, length);
 
 	// Copy application_type, application_manufacturer and manufacturer_code
-	memcpy(&state->messages[4], &state->messages[7], 5);
+	memmove(&state->messages[4], &state->messages[7], 5);
 
 	// Set string length and copy string
 	state->messages[9] = str_length;
-	memcpy(&state->messages[10], &state->messages[12], str_length);
+	memmove(&state->messages[10], &state->messages[12], str_length);
 
 	return 0;
 }