Patch merged into coreboot/master: 939dc84 crossgcc: Re-download the archive if it is incomplete

the following patch was just integrated into master:
commit 939dc8492ae80858575db3e808baf18f5ab651a0
Author: zbao 
Date:   Thu Apr 30 04:44:07 2015 +0800

crossgcc: Re-download the archive if it is incomplete

If the buildgcc is interrupt by Ctrl-C, probably part of
    an archive is downloaded. If we run buildgcc again, the
    incomplete archive would be considered as cached file
    and skipped.

We check file hashes to see if the file is complete. If test
    is failed, we need to delete the partially-downloaded file
    and download it again.

sha1sum is quite different among the distributions.
    Only Linux, Cygwin, Darwin have been tested.

Once new archive is deployed, a new checksum would be created,
    which should be uploaded along with the script buildgcc.

Change-Id: Ibb1aa25a0374f774e1e643fe5e698de7bf7cc418
    Signed-off-by: Zheng Bao 
    Signed-off-by: Zheng Bao 
    Reviewed-on: http://review.coreboot.org/4511
    Tested-by: build bot (Jenkins)
    Reviewed-by: Idwer Vollering 
    Reviewed-by: Patrick Georgi

See http://review.coreboot.org/4511 for details.

-gerrit