[feature-wisun] Added Wi-SUN interface and Border Router API.

[debdeep-arm]

Summary of changes

-Taken modification for adding IID in BR info structure.
-Added API to get RPL info for Wi-SUN router and BR.
-Added API to get routing table info from BR.

Impact of changes

Migration actions required

Documentation

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Pull request type

[] Patch update (Bug fix / Target update / Docs update / Test update / Refactor)
[X] Feature update (New feature / Functionality change / New API)
[] Major update (Breaking change E.g. Return code change / API behaviour change)

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Test results

[] No Tests required for this change (E.g docs only update)
[x] Covered by existing mbed-os tests (Greentea or Unittest)
[] Tests / results supplied as part of this PR

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Reviewers

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[ciarmcom]

@debdeep-arm, thank you for your changes.
@ARMmbed/mbed-os-maintainers please review.

[mikter]

You need to read the instance id using RPL functions as it might change

[debdeep-arm]

Should I read instance ID like this ?

mbed-os/features/nanostack/sal-stack-nanostack/source/6LoWPAN/Bootstraps/Generic/protocol_6lowpan.c

Lines 696 to 725 in 72fa02d

	uint8_t instance_id_list[10];
	uint8_t rpl_instance_count;
	uint8_t instance_id = RPL_INSTANCE_LOCAL;
	uint8_t instance_id_new;
	uint8_t instance_index;
	rpl_instance_count = rpl_instance_list_read(&instance_id_list[0], sizeof(instance_id_list));
	/* Find lowest global instance ID (assumption: RPL instance with lowest instance ID has
	most generic routing rule and its rank should be indicated in beacon) */
	for (instance_index = 0; instance_index < rpl_instance_count; instance_index++) {
	instance_id_new = instance_id_list[instance_index];
	if ((instance_id_new & RPL_INSTANCE_LOCAL) == RPL_INSTANCE_LOCAL) {
	break;
	} else {
	if (instance_id_new < instance_id) {
	instance_id = instance_id_new;
	}
	}
	}
	// Get DAG rank
	if (instance_id == RPL_INSTANCE_LOCAL) {
	return 255;
	}
	rpl_dodag_info_t rpl_dodag_info;
	if (!rpl_read_dodag_info(&rpl_dodag_info, instance_id)) {
	return 255;
	}

[mikter]

@kjbracey-arm Could you help us a bit what is the rule for selecting the instance id is this the correct way or is there something simpler?

Pull request has been modified.

[debdeep-arm]

Notifying @jk-arm

[artokin]

@0xc0170 , @adbridge , would you please start CI run for this PR?

[adbridge]

@debdeep-arm please fill in the PR header correctly as per the guidelines. You have not specified the PR type of the testing required.

[mbed-ci]

Test run: SUCCESS

Summary: 11 of 11 test jobs passed
Build number : 1
Build artifacts