This PR enables kernel modules for various USB Gadget applications for rockchip 32 bit platforms (rk322x, rk3288) for both current 6.6 and edge 6.7 kernels.

Also provides a bunch of patches to address issues with rk322x, whose peripheral mode does not really well with dwc2 driver yet. A couple of patches are self-produced after trial-and-error sessions, another pair are imported from rockchip 5.10 kernel and substitutes an older patch with a bit more refined code (see the "debounce" patch).

edit: the patches addressing the rk322x issues probably are worth also for rk3318 and rk3328, since the controller is the very same with similar issues. During my tests, I quickly checked an rk3318 device and found it has the same behaviour (disconnection, system freeze, ...). I will do further tests and, in case, import the same patches for rockchip64 too.

Jira reference number AR-2096

How Has This Been Tested?

• [x] Installed on live rk322x system, tested mass storage :heavy_check_mark:, ethernet :heavy_check_mark:, uac1/2 :negative_squared_cross_mark:
• [x] Installed on live rk3288 system in OTG mode, tested mass storage :heavy_check_mark:, uac1/2 :heavy_check_mark:

For sake of curiosity, iperf3 run on rk322x in ethernet gadget mode:

Checklist:

• [x] My code follows the style guidelines of this project
• [x] I have performed a self-review of my own code
• [x] I have commented my code, particularly in hard-to-understand areas
• [x] I have made corresponding changes to the documentation
• [x] My changes generate no new warnings
• [x] Any dependent changes have been merged and published in downstream modules

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