Fix the BTS_Tests_LAPDm.TC_t200_n200 test

The test failed, because testing retransmit timeout on DCCH would take
longer than guard timer. Instead of changing that timer, I decided to
use ACCH instead. Additional changes were required to make ACCH test
work properly.

https://osmocom.org/issues/5972

Change-Id: I2c328219b1a37d0f4623c5728143cd91976000a0
1 file changed