Season pork on all sides with 1 tablespoon rosemary, 3/4 teaspoon salt and 1/2 teaspoon pepper. Add oil to a programmable pressure multicooker (such as Instant Pot). Select Sauté setting. Select High temperature setting, and allow to preheat. Add the pork; cook on all sides until nicely browned, about 3 minutes per side. Transfer to a plate. Pour off excess drippings in the cooker; do not wipe the cooker clean. Add onion, garlic, 1/2 teaspoon rosemary and the remaining 1/2 teaspoon each salt and pepper to the cooker; cook, stirring constantly, until the onion softens, about 1 minute. Add broth, stirring to scrape up any browned bits from the bottom of the cooker.