[Test] Remove incorrect test in GVN

Removed it because it runs indvars after GVN and
it's obvious it's an indvars test, not GVN.

Also the removed test file includes a 'target triple' with aarch64 specified,
which is needed for indvars to eliminate the Phis produced by GVN,
and the test directory doesn't have a lit config to exclude lit from
running the test if aarch64 is not supported by a build.