- Remove *_masked() functions as noted by Wolfgang

- Adapt register naming to recent TI spec (sprue26, March 2007)
- Fix reset_timer() handling
- As reported by Pieter [1] the overflow fix introduced a
delay of factor 16 (e.g 2 seconds became 32). While the
overflow fix is basically okay, it missed to divide udelay by
16, too. Fix this.
[1] http://article.gmane.org/gmane.comp.boot-loaders.u-boot/38179


- Remove software division of timer count value (DIV(x)
macro) and do it in hardware (TIM_CLK_DIV).
Many thanks to Troy Kisky <troy.kisky@boundarydevices.com>
and Pieter Voorthuijsen <pieter.voorthuijsen@Prodrive.nl> for
the hints & testing!

Signed-off-by: Dirk Behme <dirk.behme@gmail.com>

Acked-by: Pieter Voorthuijsen <pieter.voorthuijsen@Prodrive.nl>