Add a test log for htrun

[k-stachowiak]

This PR adds a log pattern to be fed into htrun for comparison.

The proposed log pattern verifies that:

• serial number has been printed
• two SHA-256 tests were ran successfully

[Patater]

LGTM

I was able to test this with mbedhtrun successfully, too.

mbedhtrun -d /media/DAPLINK -p /dev/ttyACM0 -m K64F -f ./BUILD/K64F/GCC_ARM/mbed-os-example-atecc608a-tmp.bin --compare-log ./tests/atecc608a.log 
[1557845285.31][HTST][INF] host test executor ver. 0.0.1
[1557845285.31][HTST][INF] copy image onto target...
[1557845293.23][MBED][WRN] Target ID not found: Skipping flash check and retry
[1557845293.23][HTST][INF] starting host test process...
[1557845293.23][CONN][INF] starting connection process...
[1557845293.23][CONN][INF] notify event queue about extra 60 sec timeout for serial port pooling
[1557845293.23][CONN][INF] initializing serial port listener... 
[1557845293.23][SERI][INF] serial(port=/dev/ttyACM0, baudrate=9600, read_timeout=0.01, write_timeout=5)
[1557845293.23][HTST][INF] setting timeout to: 60 sec
[1557845293.23][SERI][INF] reset device using 'default' plugin...
[1557845293.34][SERI][INF] waiting 1.00 sec after reset
[1557845294.34][SERI][INF] wait for it...
[1557845294.34][SERI][TXD] mbedmbedmbedmbedmbedmbedmbedmbedmbedmbed
[1557845294.34][CONN][INF] sending up to 2 __sync packets (specified with --sync=2)
[1557845294.34][CONN][INF] sending preamble '5be93f4d-7cf4-434b-9ac4-1e5f2254f348'
[1557845294.34][SERI][TXD] {{__sync;5be93f4d-7cf4-434b-9ac4-1e5f2254f348}}
[1557845294.35][CONN][RXD] **********************************************
[1557845294.35][CONN][RXD] Serial Number:
[1557845294.35][CONN][RXD] 01 23 BA CF BA D3 29 CA EE 
[1557845294.35][CONN][RXD] 
[1557845294.35][CONN][RXD] **********************************************
[1557845294.35][CONN][RXD] SHA-256:
[1557845294.35][CONN][RXD] 
[1557845294.35][CONN][RXD] Input: 61 62 63 
[1557845294.35][CONN][RXD] Expected Hash: BA 78 16 BF 8F 01 CF EA 41 41 40 DE 5D AE 22 23 
[1557845294.35][CONN][RXD] B0 03 61 A3 96 17 7A 9C B4 10 FF 61 F2 00 15 AD 
[1557845294.35][CONN][RXD] 
[1557845294.35][CONN][RXD] Actual Hash: BA 78 16 BF 8F 01 CF EA 41 41 40 DE 5D AE 22 23 
[1557845294.35][CONN][RXD] B0 03 61 A3 96 17 7A 9C B4 10 FF 61 F2 00 15 AD 
[1557845294.35][CONN][RXD] 
[1557845294.35][CONN][RXD] Success!
[1557845294.36][CONN][RXD] 
[1557845294.36][CONN][RXD] **********************************************
[1557845294.36][CONN][RXD] SHA-256:
[1557845294.36][CONN][RXD] 
[1557845294.36][CONN][RXD] Input: 
[1557845294.36][CONN][RXD] Expected Hash: E3 B0 C4 42 98 FC 1C 14 9A FB F4 C8 99 6F B9 24 
[1557845294.36][CONN][RXD] 27 AE 41 E4 64 9B 93 4C A4 95 99 1B 78 52 B8 55 
[1557845294.36][CONN][RXD] 
[1557845294.36][CONN][RXD] Actual Hash: E3 B0 C4 42 98 FC 1C 14 9A FB F4 C8 99 6F B9 24 
[1557845294.36][CONN][RXD] 27 AE 41 E4 64 9B 93 4C A4 95 99 1B 78 52 B8 55 
[1557845294.36][CONN][RXD] 
[1557845294.36][CONN][RXD] Success!
[1557845294.36][CONN][RXD] 
[1557845294.36][HTST][INF] Target log matches compare log!
[1557845294.36][HTST][INF] test suite run finished after 1.12 sec...
[1557845294.37][CONN][INF] received special event '__host_test_finished' value='True', finishing
[1557845294.37][HTST][INF] CONN exited with code: 0
[1557845294.37][HTST][INF] Some events in queue
[1557845294.37][HTST][INF] stopped consuming events
[1557845294.37][HTST][INF] host test result() call skipped, received: True
[1557845294.37][HTST][WRN] missing __exit event from DUT
[1557845294.37][HTST][WRN] missing __exit_event_queue event from host test
[1557845294.37][HTST][INF] calling blocking teardown()
[1557845294.37][HTST][INF] teardown() finished
[1557845294.37][HTST][INF] {{result;success}}