Add ->tmu_clear_irqs method to struct exynos_tmu_data and use
it instead exynos_tmu_clear_irqs(). Then add ->tmu_clear_irqs
implementations for Exynos4210+ and Exynos5440. Finally
remove no longer needed reg->tmu_int[stat,clear] abstractions
and struct exynos_tmu_registers instances.
There should be no functional changes caused by this patch.