[mlir][spirv] Add a pass to deduce version/extension/capability

Creates an operation pass that deduces and attaches the minimal version/
capabilities/extensions requirements for spv.module ops.

For each spv.module op, this pass requires a `spv.target_env` attribute on
it or an enclosing module-like op to drive the deduction. The reason is
that an op can be enabled by multiple extensions/capabilities. So we need
to know which one to pick. `spv.target_env` gives the hard limit as for
what the target environment can support; this pass deduces what are
actually needed for a specific spv.module op.

Differential Revision: https://reviews.llvm.org/D75870