ARM: davinci: Drop unneeded select of TIMER_OF

Support for TI DaVinci SoCs depends on ARCH_MULTI_V5, and thus on
ARCH_MULTIPLATFORM.
As the latter selects TIMER_OF, there is no need for MACH_DA8XX_DT to
select TIMER_OF.

Link: https://lore.kernel.org/r/20200505150722.1575-9-geert+renesas@glider.be


Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Cc: Sekhar Nori <nsekhar@ti.com>
Cc: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Sekhar Nori <nsekhar@ti.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>