arm: omap2: timer: get rid of obfuscating macros

those macros just make it a lot more difficult
to grep around and actually find similarities.

In this patch, we will simply remove them and
replace with actual functions and later commits
will come to further clean this up.

Signed-off-by: Felipe Balbi <balbi@ti.com>

diff --cc arch/arm/mach-omap2/timer.c
Simple merge