ARM: OMAP2+: Drop old timer code for dmtimer and 32k counter

With dmtimer and 32k counter being initialized based on devicetree data,
we can just drop the old timer code.

This still leaves the omap5 and dra7 realtime_counter_init() that
depend on the smc calls and control module platform code for the dra7
quirk init.

Cc: Grygorii Strashko <grygorii.strashko@ti.com>
Cc: Keerthy <j-keerthy@ti.com>
Cc: Lokesh Vutla <lokeshvutla@ti.com>
Cc: Rob Herring <robh@kernel.org>
Cc: Tero Kristo <t-kristo@ti.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>