This patch enables SDEI support for all Tegra platforms, with
the following configuration settings.

* SGI 8 as the source IRQ
* Special Private Event 0
* Three private, dynamic events
* Three shared, dynamic events
* Twelve general purpose explicit events

Verified using TFTF SDEI test suite.

******************************* Summary *******************************
 Test suite 'SDEI'                                               Passed
 =================================
 Tests Skipped : 0
 Tests Passed  : 5
 Tests Failed  : 0
 Tests Crashed : 0
 Total tests   : 5
 =================================

Signed-off-by: Varun Wadekar <vwadekar@nvidia.com>
Change-Id: I1922069931a7876a4594e53260ee09f2e4f09390