ti-eula-unpack: Force Console Mode, add Error Prints

ti-eula-unpack: Force Console Mode, add Error Prints

   * ti-eula-unpack runs installjammer installers to install ti components
   * installjammer can run in GUI mode or console mode
   * ti-eula-unpack passes options and string paths to the installer
     which need to be run in console mode
   * GUI mode is automatically selected if an X11 Display is found which
     means that script options won't get passed to the installer

   * This patch forces use of console mode in the installer, so that the
     GUI will never be invoked for these scripted installs even if an X
     Display is found

   * Downside is ti-eula-unpack is now tighter coupled to installjammer, but
     all current ti installers are ij based so not an issue currently

   * Extra error checks and prints added with failure returns on error
   * This also helps if the installer can't run, for example if run on
     64bit host without 32bit compat libs (currently required by these
     installjammer installers)

Signed-off-by: Roger Monk <r-monk@ti.com>
Signed-off-by: Koen Kooi <k-kooi@ti.com>