Tegra186: introduce platform support

This patch introduces initial support for Tegra186 platforms.

Verified with tftf-validation.

******************************* Summary *******************************
> Test suite 'Framework Validation'
                                                                Passed
> Test suite 'Timer framework Validation'
                                                                Passed
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Tests Skipped : 0
Tests Passed  : 6
Tests Failed  : 0
Tests Crashed : 0
Total tests   : 6
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Signed-off-by: Varun Wadekar <vwadekar@nvidia.com>
Change-Id: I9c68fce2cbc14592dbb2738adbeb64ec33e910e8
9 files changed