Disable screen blanking and powersave on VT2 for factory

Disable screen blanking and powersave on VT2 for factory

BUG=chrome-os-partner:2950
TEST=manual,
1. create factory image place on USB stick
2. boot to 'dev' screen hit ctrl-U
3. run factory flow ( wouldn't complete on my system )
4. switch to VT2 and make sure screen stays on >10min
5. switch to VT1 (factory test) make sure still operational
6. switch to VT2, and sudo stop factory
7. make sure VT2 screen stays on >10min

Change-Id: Id01a7938bfd4e2abbddfd0ff6856649cc853b737

Committed: http://chrome-svn/viewvc/chromeos?view=rev&revision=3dfb741

[tbroch1, 2011-04-13 17:24:20]

Tried this change on partner device referenced by crosbug.com/p/2950 as
described in TEST=

Tried just issuing 'echo' at VT2 prompt on two other devices to make sure
desired affect there as well.

Thanks for reviewing.

[Hung-Te, 2011-04-13 17:55:19]

LGTM

Maybe we'll need to spread this into many other locations in future, for example
the factory installer, and the wiping command...