AMDGPU: Add regression testcase for bundle pressure issue

This is a somewhat reduced testcase that regressed, causing the revert
in 477e3fe4f874b1c4d5896f3bfaf7b3b8a6d38103.

This was producing a bundle that could not be allocated. This is a
tricky one to reduce/reproduce, but I do like having some sanity check
for this.

GitOrigin-RevId: 27093f1a94e2bb95400dfc5407b581aacb401951
1 file changed