USB Storage Sierra: TRU-Install feature update

USB Storage Sierra: TRU-Install feature update

This patch upgrades the support for the Sierra Wireless TRU-Install
feature (i.e. zeroCD) to allow for future support of Linux enabled
TRU-Install devices.

By default all devices that do not have a Linux enabled TRU-Install
device (i.e. the device does not have a Linux package on the virtual CD
partition) will be switched into "modem mode." Devices that do contain a
Linux package in the TRU-Install virtual CD will be allowed to enumerate
as a CD-Rom so that either (a) a user can install the packaged software
or (b) a user-space application (e.g. udev) can switch it to modem mode.

This patch does allow for manual override by adding a usb-storage module
parameter 'swi_tru_install' which can force the modem into either mode
regardless of what packages it contains.

Signed-off-by: Kevin Lloyd <klloyd@sierrawireless.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>