Pelion enable for UNO_91H

[fredlee12001]

Description (required)

Fix multi issues for UNO_91H when integrate pelion.

Summary of change (What the change is for and why)

1, Modify Clock setting
2, Update wifi driver from UNISOC.
3, UART driver logic error.

Documentation (Details of any document updates required)

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Pull request type (required)

[x] Patch update (Bug fix / Target update / Docs update / Test update / Refactor)
[] 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 (required)

[] 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 (optional)

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Release Notes (required for feature/major PRs)

Summary of changes

Impact of changes

Migration actions required

[ciarmcom]

@fredlee12001, thank you for your changes.
@ARMmbed/mbed-os-ipcore @ARMmbed/mbed-os-maintainers please review.

[0xc0170]

CI started

[mbed-ci]

Test run: FAILED

Summary: 3 of 4 test jobs failed
Build number : 1
Build artifacts

Failed test jobs:

• jenkins-ci/mbed-os-ci_build-ARM
• jenkins-ci/mbed-os-ci_build-IAR
• jenkins-ci/mbed-os-ci_build-GCC_ARM

[0xc0170]

@fredlee12001 Please review failures

device/system_RDA5991H.c:177:17: error: use of undeclared identifier 'APPLICATION_ADDR'
    SCB->VTOR = APPLICATION_ADDR;

[fredlee12001]

Missed the point that APPLICATION_ADDR only defined when "restrict_size" given in json.
Add the default value for APPLICATION_ADDR to fix the issue. Verified locally and works all fine now.

[0xc0170]

CI started

[mbed-ci]

Test run: SUCCESS

Summary: 11 of 11 test jobs passed
Build number : 2
Build artifacts