[U-Boot] Backport of qi ext2 patches

[Sven 'sleipnir' Rebhan]

Hi List,

after the change at projects.openmoko.org I suddenly had some spare
time and invested it in porting back the Qi changes to the ext2
filesystem handles. The patches are basically taken from Andy's posts
here

http://www.mail-archive.com/openmoko-kernel@lists.openmoko.org/msg05705.html
http://www.mail-archive.com/openmoko-kernel@lists.openmoko.org/msg05708.html

With the patches the loading time of the kernel from the ext2 SDCard
dropped. Unfortunaltly I had not yet the time to do intensive tests,
but at least U-Boot behaves as usual. The measured times:
U-Boot 1.3.2-moko12 (Aug 26 2008 - 08:24:58)					     0m7.498s
U-Boot 1.3.2-dirty-moko12 (Dec 17 2008 - 22:33:35)				   0m7.592s
U-Boot 1.3.2-dirty-moko12 (Dec 17 2008 - 22:33:35) ext2-fix		      0m5.426s
U-Boot 1.3.2-dirty-moko12 (Dec 17 2008 - 23:30:48) ext2-fix-optimized	0m5.445s

The setting was the following (including a rootdelay=5):

menu_3=Boot from NFS (Gentoo): setenv bootargs ${bootargs_nfs}
${mtdparts}; mmcinit; ext2load mmc 0 0x32000000
/boot/uImage-2.6.24.sleipnir; bootm 0x320000
bootargs_nfs=root=/dev/nfs nfsroot=192.168.0.200:/nfsexports/Gentoo
ip=192.168.0.202:192.168.0.200::255.255.255.0:Hugin:usb0:off
rootdelay=5 console=tty0

Best regards,

  Sven 'sleipnir' Rebhan