tests: add core_setmaster_vs_auth

Tests that master state isn't leaked to new masters by checking
that auth magics for the old master don't work any more.

Based upon a simple test program provided by Thomas.

v2: Use comment Thomas suggested on intel-gfx.

Cc: Thomas Hellstrom <thellstrom@vmware.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
2 files changed