Bug fix for receive windows

[hasnainvirk]

Description

In rx_config(params) API we shouldn't check for radio state as radio may never get
idle for a class C device. That check made sense only for class A. As the PHY layer
have no conecpt of receive windows which is a MAC layer construct, we should remove the
state check.
The API will be changed later to void rx_config(params).

In addition to that another bug is fixed in the open_rx2_windows() API. We should set the rx slot
first before instantiating a test based on its value.

Pull request type

[X] Fix
[ ] Refactor
[ ] New target
[ ] Feature
[ ] Breaking change

[hasnainvirk]

@kivaisan @AnttiKauppila @kjbracey-arm Please review.

[0xc0170]

/morph build

[mbed-ci]

Build : SUCCESS

Build number : 2503
Build artifacts/logs : http://mbed-os.s3-website-eu-west-1.amazonaws.com/?prefix=builds/7399/

Triggering tests

/morph test
/morph uvisor-test
/morph export-build
/morph mbed2-build

[hasnainvirk]

@0xc0170 We will need to redeploy CI for this PR. Aborted for exporter test for some reason.

[mbed-ci]

Test : SUCCESS

Build number : 2279
Test logs :http://mbed-os-logs.s3-website-us-west-1.amazonaws.com/?prefix=logs/7399/2279

[hasnainvirk]

@OPpuolitaival Can you please tell me why is the exporter build failing ?

[0xc0170]

/morph export-build

[mbed-ci]

Exporter Build : FAILURE

Build number : 2159
Build artifacts/logs : http://mbed-os.s3-website-eu-west-1.amazonaws.com/?prefix=builds/exporter/7399/

[0xc0170]

/morph export-build

[mbed-ci]

Exporter Build : SUCCESS

Build number : 2167
Build artifacts/logs : http://mbed-os.s3-website-eu-west-1.amazonaws.com/?prefix=builds/exporter/7399/

[cmonr]

The use of _lora_phy.handle_receive(); is throwing this to 5.10.