OMAP-TEST: TIMER: Fixes for Linux v3.8

For Linux v3.8 the definitions OMAP2_DEVICE_TYPE_GP and soc_is_am335x()
are not defined for OMAP1 devices and so generated compilation warnings.
Given that we cannot support both OMAP1 and OMAP2+ devices in a single
kernel image, workaround this by using the CONFIG_ARCH_OMAP1 kernel
option at compile time.

Signed-off-by: Jon Hunter <jon-hunter@ti.com>
OMAP-TEST: TIMER: Add Request Test

Add a timer request test to test the timer request APIs ...

- omap_dm_timer_request()
- omap_dm_timer_request_by_cap()
- omap_dm_timer_request_specific()

Note that omap_dm_timer_request_specific() is not supported when device
tree is present and so is only tested when booting without device tree.

Signed-off-by: Jon Hunter <jon-hunter@ti.com>
OMAP-TEST: TIMER: Add match interrupt test

Adds test for timer match interrupt feature.

Signed-off-by: Jon Hunter <jon-hunter@ti.com>
OMAP-TEST: TIMER: Interrupt fixes

Several minor interrupt fixes for the timer tests, including ...

1. Using the new omap_dm_timer_set_int_disable() API to disable
   interrupts instead of the omap_dm_timer_set_int_enable() API because
   this API does not work for all timer instances.
2. Disable interrupts prior to stopping the timer, so there is no chance
   of an interrupt occurring just as we are stopping the timer and
   generating an exception because the clocks are disabled when the
   interrupt handler runs.
3. Only acknowledge the interrupt, if a valid interrupt occurred.

Signed-off-by: Jon Hunter <jon-hunter@ti.com>
OMAP-TEST: Add README

Add README file with build and usage instructions.

Signed-off-by: Jon Hunter <jon-hunter@ti.com>
update request test
remove unnecessary function
misc cleanup