Mount /dev/fs/9fat if available

Reference: /n/sources/patch/applied/9fat_devfs
Date: Sat Nov 26 13:57:49 CET 2005

--- /rc/bin/9fat:	Sat Nov 26 13:57:34 2005
+++ /rc/bin/9fat:	Sat Nov 26 13:57:30 2005
@@ -1,7 +1,7 @@
 #!/bin/rc
 
 rfork e
-part=`{ls /dev/sd*/9fat >[2]/dev/null}
+part=`{ls /dev/fs/9fat /dev/sd*/9fat >[2]/dev/null}
 if(~ $#part 0) {
 	echo 'no 9fat partition found' >[1=2]
 	exit no.9fat