[XLA] Fix contiguous allocations when the position has two separate uses and the second use cannot be placed in the alternate memory.
[XLA] Fix contiguous allocations when the position has two separate uses and the second use cannot be placed in the alternate memory.

Also added a verification to ensure there are no multiple pinned allocations.

Reverts changelist 641225077

FUTURE_COPYBARA_INTEGRATE_REVIEW=https://github.com/openxla/xla/pull/13523 from ROCm:ci_hotfit_20240607 931ddf1d5b87c85c3fe1d825665015882d50ef42
