Add fix for Timer test - provide missing get_info ticker interface fu…

[mprse]

Description

This commit provides fix for Timer test.
Ticker interface has changed.

Status

READY

Migrations

NO

Todos

• Extend test to verify if Timer correctly converts ticker ticks to time (us) based on ticker frequency.

[0xc0170]

Tested locally, all passing for NRF51 DK that was failing without this patch (tested GCC ARM and ARM)

[mbed-ci]

Build : SUCCESS

Build number : 189
Build artifacts/logs : http://mbed-os.s3-website-eu-west-1.amazonaws.com/?prefix=builds/5325/

Triggering tests

/morph test

[mbed-ci]

Test : SUCCESS

Build number : 90
Test logs :http://mbed-os-logs.s3-website-us-west-1.amazonaws.com/?prefix=logs/5325/90

[orenc17]

retest uvisor 5325

[orenc17]

retest uvisor 5325

[0xc0170]

AWS-CI uVisor Build & Test - is green, the old status AWS-CI uVisor Build & Test mbedos-5325 is a result of an old infrastructure.

Ready for integration

[adbridge]

Reliant on #5028