fix bug for RDA UNO_91H：calling us ticker functions without init.

[caixue1102]

Description

fix bug for RDA UNO_91H：calling us ticker functions without init.
solution: init us ticker when init TRNG, because we use us ticker read to delay and wait for TRNG seed ready.

Pull request type

[x] Fix
[ ] Refactor
[ ] Target update
[ ] Functionality change
[ ] Docs update
[ ] Test update
[ ] Breaking change

Reviewers

[0xc0170]

Can you review travis build failure in docs:
$ find "(" -name "*.a" -or -name "*.ar" ")" -and -not -name "lib*" | tee BUILD/badlibs | sed -e "s/^/Bad library name found: /" && [ ! -s BUILD/badlibs ]

Another request is to use Description to describe your pull request. I'll paste here an example

Description

Add support wifi for RDA target

Tested with GCC ARM, IAR and ARMCC.

Test report here: `paste here test results

[SeppoTakalo]

Please specify the target name in commit message and Pull-Request title. Otherwise this is a bit misleading.

Also, please submit a test results when running Socket, Wifi + EMAC tests against current Mbed OS master.
These are documented in:

• https://os.mbed.com/docs/v5.11/porting/wifi-port.html
• https://os.mbed.com/docs/v5.11/porting/ethernet-port.html#testing
• https://github.com/ARMmbed/mbed-os/blob/master/TESTS/netsocket/README.md
• https://github.com/ARMmbed/mbed-os/blob/master/TESTS/network/emac/README.md

[0xc0170]

@caixue1102 Let us know if you need any assistance

[kyliuxing]

@0xc0170 We need fix a TRNG bug before support wifi for UNO_91H. Please help review it. Thanks.

[0xc0170]

Looks fine to me, one question: why are we initalizing us ticker in TRNG ?

[0xc0170]

Simple fix but not clear to a reader how is TRNG related to us ticker - what bug is this fixing - can you add this to the commit msg?

Travis failure will be fixed via rebase, we can help there once the last fix is on master (today)

[caixue1102]

We use us ticker delay to waiting for TRNG seed ready, and we do this to avoid calling us ticker functions without us_ticker_init.

[0xc0170]

We will rebase once travis is done and start CI

[cmonr]

NOTE: This PR has now been rebased.

If this was made in error, feel free to force-push your local branch to restore the PR.

[0xc0170]

CI started

[mbed-ci]

Test run: FAILED

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

Failed test jobs:

• jenkins-ci/mbed-os-ci_greentea-test

[caixue1102]

Thank you for the test, but I can't find the failed test job in the link, so that I don't know the relationship with my commit. Could you please give me some pointers.

[0xc0170]

Build artifacts

You can find it linked above via Build artifacts.

I restarted teh test as this was an issue with CI job itself, restarted

[0xc0170]

CI restarted