Update base for Update on "Add xplat cxx_binary target for bench_sdpa"

Add non_fbcode_target cxx_binary so bench_sdpa can be built via the
xplat build path (e.g. for on-device testing). Wrap the existing
cpp_benchmark in fbcode_target to avoid name collision between the
fbcode benchmark target and the xplat binary target.

Differential Revision: [D96044315](https://our.internmc.facebook.com/intern/diff/D96044315/)

[ghstack-poisoned]

Author: kimishpatel