[wiring] BLE: return false if expected characteristic is not found.

[XuGuohui]

Problem

getCharacteristicByDescription() return true even if there is no characteristic is matched.

Solution

return false if there is no characteristic matches the given description.

Example App

N/A

References

N/A

Completeness

• User is totes amazing for contributing!
• Contributor has signed CLA (Info here)
• Problem and Solution clearly stated
• Run unit/integration/application tests on device
• Added documentation
• Added to CHANGELOG.md after merging (add links to docs and issues)