Ensure variable names do not clash with Coq keywords.

examples/proofs/binary_search/generated_code.v

examples/proofs/binary_search/generated_proof_test.v

examples/proofs/btree/generated_code.v

examples/proofs/btree/generated_proof_btree_member.v

examples/proofs/btree/generated_proof_free_btree.v

examples/proofs/btree/generated_proof_new_btree.v

examples/proofs/lock/generated_code.v

examples/proofs/lock/generated_proof_increment.v

examples/proofs/lock/generated_proof_init.v

examples/proofs/lock/generated_proof_read_locked.v

examples/proofs/lock/generated_proof_write_locked.v

examples/proofs/mpool/generated_code.v

examples/proofs/mpool/generated_proof_mpool_add_chunk.v

examples/proofs/mpool/generated_proof_mpool_alloc.v

...les/proofs/mpool/generated_proof_mpool_alloc_contiguous.v

...pool/generated_proof_mpool_alloc_contiguous_no_fallback.v

...es/proofs/mpool/generated_proof_mpool_alloc_no_fallback.v

examples/proofs/mpool/generated_proof_mpool_fini.v

examples/proofs/mpool/generated_proof_mpool_free.v

examples/proofs/mpool/generated_proof_mpool_init.v