Drop "sleep 3" from sdelay if CDROOT=1. One can use scandelay=secs if needed.

While this makes out of the box booting a bit harder on some ancient CD/DVD
drives, it really speeds up the common use case by not sleeping for 3 seconds.

defaults/initrd.scripts

@@ -991,19 +991,13 @@ startLUKS() {
 
 sdelay() {
 	# Sleep a specific number of seconds if SDELAY is set
-	if [ "${SDELAY}" ]
+	if [ -n "${SDELAY}" ]
 	then
 		good_msg "Waiting ${SDELAY} seconds..."
 		sleep ${SDELAY}
 	elif [ "${CDROOT}" = '1' ]
 	then
-		# many CD/DVD drives require extra sleep, especially when
-		# connected via USB. Many people reported that 1 second sleep
-		# is not enough on their notebooks, that's why sleep 3, when booting
-		# off a livecd is a better default.
-		sleep 3
-	else
-		good_msg 'Hint: Use parameter scandelay[=seconds] if you need waiting here'
+		good_msg 'Hint: Use scandelay[=seconds] if your live medium is slowand boot fails'
 	fi
 }