LPC55S69 support in Mbed OS 6

[willlordarm (Will Lord)]

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How to use mbed os 6.5 for LPC55S69

Unfortunately, the mbed team has discontinued support for the mbed os 6 series on the LPC55S69. However, according to my research, it was supported up to 6.5. 13921 TARGET_NXP: Remove support for LPC55S69 For reasons unknown, it is now supported up to 5.15. Therefore, when we install 6.5, mbed cli get an unsupported error when compiling. However, the source code for 6.5 still contains the necessary hardware information for LPC55S69. Mbed team most likely verified the operation test at le…