goldfish-opengl: nuke virtualizationSupported

Not used after removing canFitVirtualHostVisibleMemoryInfo in
c01d77414cd7.

usingDirectMapping is redundant BTW and can also be removed in
the future.

BUG=233803018
TEST=compile

Change-Id: Ie7e34f99a572a7bb9ca07c8f63883756ae2213b1
3 files changed