SF: Remove unused property of test DisplayVariant

Bug: 241285876
Test: m libsurfaceflinger_unittest
Change-Id: If5f4a7b44812a6a9b2fcc5ba423de14596b717f2
Merged-In: If5f4a7b44812a6a9b2fcc5ba423de14596b717f2
(cherry picked from commit 36cface18f0eb2d5fe4d479110695ef053a0f402)
1 file changed