Add ohos code in the cmakelist file for cross compilation of OpenHarmony

[SC404]

PR devices

Framework OpenHarmony

PR types

Performance optimization

PR changes

Build

Description

we are using Paddle-lite lib in OpenHarmony, so we'd like to contribute the build guide, hope it can help developers.

[paddle-bot]

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[CLAassistant]

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[hong19860320]

Thank you for your contribution. You need to sign the Contributor License Agreement (CLA) first, and then wait for the Continuous Integration (CI) process to complete.