SEATTLE — Want a number that will make you happy? Here’s one: 90. That’s how many games the Mariners won last year without Cy Young winner Robbie Ray and former All-Stars Jesse Winker, Eugenio Suárez and Adam Frazier. Those are the big names Seattle general manager Jerry Dipoto added to the roster this offseason. Want another one? Here you go: One. That’s the ranking Baseball America gave to the Mariners’ farm system two months ago — a system that is still teeming with talent. I’ll throw you another goody: 12. That’s the number of MLB teams that will make the postseason this year, which could …