PC-12 pilot reported a passenger reported seeing smoke under a seat shortly before landing. Pilot continued to safe landing.

Narrative

Coming back from ZZZ1; I experienced a system failure that resulted in [requesting priority handling].We intercepted the ILS XX course and was cleared for the approach. As I decelerated on the localizer; I selected Flaps to 15 degrees. This is common for an instrument approach in the PC-12. As the flaps made into 15; I got a master caution on the warning CAWS (Central Advisory & Warning System) panel. 'Flaps' Amber Annunciator was illuminated. A few moments later; I was 1/2 dot from GS intercept and selected gear down. As I confirmed 3 green indications ; I heard one of passengers say 'There's smoke from under a seat!' My brother in law; who's a Captain for a 121 Carrier; was sitting in the copilot seat. When he turned to look; he didn't see any smoke. However; both of us could smell the smoke. I [requested priority handling] with ZZZ tower. I was inside the FAF with the gear down; the runway was in front of us. I made the decision to 'just get it on the ground.'On short final; I asked tower to relay to an aircraft that was holding short to ask see if they could see any smoke coming from the plane. They said negative. The tower also confirmed that they didn't see any smoke coming from the plane. On rollout and taxi off; CFR (Crash Fire Rescue) was in position. We exited the runway at taxiway 1. CFR inspected the plane and didn't see any smoke. I made the decision to continue to taxi to the FBO. We shut down the plane; and exited the main cabin door and spoke to the rescue personnel. After everyone exited; I inspected the interior and could smell the light smoke odor from the seat that the passenger identified the smoke. In the cockpit; I did see the Flap CB (Circuit Breaker) had tripped. I attributed this to the Flap Motor/Power Drive Unit being in an overtemp condition.