Wip/d4s/t5472

Add initial support of rollback/upgrade mechanism for mx6qsabrelite board.

added 4 commits

• 9801f261 - 1 commit from branch master
• 2dc74f80 - Configure rollback support
• 00bf0d80 - mx6qsabrelite: add board-specific setup script
• dc1d6008 - mx6qsabrelite: enable board-specific configuration

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added 2 commits

• 337d1650 - mx6qsabrelite: add board-specific setup script
• adfe7069 - mx6qsabrelite: enable board-specific configuration

Compare with previous version

added 1 commit

• dcc7edaf - Add u-boot-tools package

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merged