Add SystemDescriptor test to VtsSecurityAvb

The test case compares device mapper table with system hashtree
descriptor. It ensures that verified boot for GSI is enabled.

Bug: 65470881
Test: vts-tradefed run vts -m VtsSecurityAvb
Change-Id: Ibd6dfab828d9eb24f7e9ed1ae91003e04e63a132
1 file changed