Move Feature struct to solana-program (#13321)

(cherry picked from commit 4b65e32f22)

Co-authored-by: Michael Vines <mvines@gmail.com>

sdk/program/src/lib.rs

@@ -12,6 +12,7 @@ pub mod decode_error;
 pub mod entrypoint;
 pub mod entrypoint_deprecated;
 pub mod epoch_schedule;
+pub mod feature;
 pub mod fee_calculator;
 pub mod hash;
 pub mod incinerator;