A workaround to make sure /dev/mtd0 can be created

A workaround to make sure /dev/mtd0 can be created when memdisk is used.
This is due to sometimes "modprobe phram" can not successfully create /dev/mtd0.
Have to try several times.
Ref: https://gitlab.gnome.org/GNOME/gparted/issues/50#note_523831
     http://gparted-forum.surf4.info/viewtopic.php?pid=32784#p32784

components/9990-main.sh

@@ -57,8 +57,19 @@ Live ()
 				if [ $? -eq 0 ]
 				then
 					# We found a memdisk, set up phram
-					modprobe phram phram=memdisk,${MEMDISK}
-					modprobe phram phram=memdisk,${MEMDISK}
+					# Sometimes "modprobe phram" can not successfully create /dev/mtd0.
+				        # Have to try several times.
+					max_try=20
+					while [ ! -c /dev/mtd0 -a "$max_try" -gt 0 ]; do
+					  modprobe phram phram=memdisk,${MEMDISK}
+					  sleep 0.2
+					  if [ -c /dev/mtd0 ]; then
+					  	break
+					  else
+					  	rmmod phram
+				  	  fi
+					  max_try=$((max_try - 1))
+					done
 
 					# Load mtdblock, the memdisk will be /dev/mtdblock0
 					modprobe mtdblock