Add memory operation syscalls (backport #16447)

[mergify]

This is an automatic backport of pull request #16447 done by Mergify.
Cherry-pick of 2b50529 has failed:

On branch mergify/bp/v1.7/pr-16447
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Changes to be committed:
	modified:   programs/bpf/Cargo.toml
	modified:   programs/bpf/build.rs
	modified:   programs/bpf/rust/mem/Cargo.toml
	new file:   programs/bpf/rust/mem/src/entrypoint.rs
	modified:   programs/bpf/rust/mem/src/lib.rs
	new file:   programs/bpf/rust/mem/tests/lib.rs
	new file:   programs/bpf/rust/membuiltins/Cargo.toml
	new file:   programs/bpf/rust/membuiltins/src/lib.rs
	modified:   programs/bpf/rust/sysvar/tests/lib.rs
	modified:   programs/bpf/tests/programs.rs
	modified:   programs/bpf_loader/src/syscalls.rs
	modified:   sdk/program/src/lib.rs
	new file:   sdk/program/src/program_memory.rs
	modified:   sdk/program/src/program_stubs.rs
	modified:   sdk/src/feature_set.rs

Unmerged paths:
  (use "git add <file>..." to mark resolution)
	both modified:   programs/bpf/Cargo.lock

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[solana-grimes]

😱 New commits were pushed while the automerge label was present.