Change this from "1A" to "60" to disable spin jumping. Unlike 0583E (SNES $00:D63E) from "10" to "80", changing this address does not make the "A" button do the regular jump, but it disables spin jumping altogether. This way, you can use the "A" button for something else without it jumping automatically.
Note: Still allows you to spinjump out of the water and dismount Yoshi.