ESPHome Drops ili9xxx, st7789v and st7735 in 2027.5.0: Migrating SPI TFTs to mipi_spi

ESPHome has now put a date on the end of its legacy SPI display drivers. Four pull requests merged on 14 October 2026 (#20687 ili9xxx, #20688 st7735, #20689 st7789v, #20690 qspi_dbi) change the deprec