How to determine gta04 hardware revision?

[Nikita V. Youshchenko]

> If you want to see the revision for informational purposes:
>
> dmesg | fgrep Revision

Relying on dmesg immediately makes software unreliable, since kernel log 
buffer may overflow

> Since the A3 board also lacks a mechanism to on/off the UMTS modem you
> can check for the presence of the GPIO that controls it:
>
> ls -l /sys/class/gpio/gpio186

Relying on GPIO number does not look good as well - numbers tent to be 
dynamic and change over time. Need to read something immutable (and kernel 
should provide that).

Nikita