Add FAT support, fix flash.sh (forgot to unmount).

board/olinuxino/linux-3.18.config

 CONFIG_PWM=y
 CONFIG_PWM_MXS=y
 CONFIG_EXT4_FS=y
+CONFIG_MSDOS_FS=y
+CONFIG_VFAT_FS=y
 CONFIG_TMPFS=y
 CONFIG_TMPFS_POSIX_ACL=y
 # CONFIG_MISC_FILESYSTEMS is not set
 # CONFIG_NETWORK_FILESYSTEMS is not set
+CONFIG_NLS_CODEPAGE_437=y
+CONFIG_NLS_ASCII=y
+CONFIG_NLS_ISO8859_1=y
+CONFIG_NLS_UTF8=y
 CONFIG_PRINTK_TIME=y
 CONFIG_FRAME_WARN=2048
 CONFIG_UNUSED_SYMBOLS=y

flash.sh

 
 	echo Copying root filesystem
 	sudo tar xfp output/images/rootfs.tar -C /media/rootfs
+
+	echo Synchronising changes to disk
+	sudo sync
+
+	echo Unmounting root filesystem
+	sudo umount /media/rootfs
+	sudo rm -rf /media/rootfs
 else
 	echo Writing root filesystem
 	sudo dd if=output/images/rootfs.ext2 of="$1"2 bs=512
-fi
 
-echo Synchronising changes to disk
-sudo sync
+	echo Synchronising changes to disk
+	sudo sync
+fi