src: Set MPTCP_PM_ADDR_FLAG_SIGNAL as needed.

[ossama-othman]

The MPTCP_PM_ADDR_FLAG_SIGNAL flag is required when a port is specified. Make sure it is set when setting flags for the given network address through through mptcpd_kpm_set_limits().

This also corrects an invalid argument (EINVAL) error exhibited by the test-commands unit test.

[coveralls]

Pull Request Test Coverage Report for Build 3048993486

Warning: This coverage report may be inaccurate.

This pull request's base commit is no longer the HEAD commit of its target branch. This means it includes changes from outside the original pull request, including, potentially, unrelated coverage changes.

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Details

• 3 of 3 (100.0%) changed or added relevant lines in 1 file are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage increased (+0.05%) to 64.739%

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Totals
Change from base Build 3040164997:	0.05%
Covered Lines:	1388
Relevant Lines:	2144

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💛 - Coveralls