Keeps alive the current USB session by informing the host device that the user cancelled an ongoing USB transfer, instead of stalling the endpoints.
Also updated the USB ABI specs once again.
* Updated usbSendCommand() to make it send the command header first, and then the command block. Makes it easier for host applications to read and parse command data.
* Let usbSendCommand() take care of handling ZLT packets if required by any command block (only SendNspHeader at this moment), as well as logging status data via usbLogStatusDetail().
* Updated USB ABI specs doc.
* gamecard: added more comments, modified gamecardGetBundledFirmwareUpdateVersion() to fill a VersionType1 pointer instead of a u32, fallback to manually reading the gamecard certificate if fsDeviceOperatorGetGameCardDeviceCertificate() fails, updated GameCardFwVersion enum.
* title: tweaked conditions for some functions.
* usb: explicitly defined values for previously omitted struct members while initializing USB comms, imported libusb structs to make it easier to work with the USB BOS, added a few more comments and changed around some code.
* utils: tweaked the illegal filesystem character array to remove some chars that are actually allowed.
Key area and certificate can be optionally appended and/or preserved, respectively. Trimming is supported.
Also added a bunch of ZLT packet related fixes to usb.c, as well as a function to properly cancel an ongoing file transfer.
* Codestyle fixes.
* NCA contexts for NCAs with titlekey crypto will now be generated even if the ticket can't be retrieved, in order to be able to use ncaReadContentFile() with them.
* Moved aes128XtsNintendoCrypt() out of nca.c.
* Updated disclaimer in all source files.
* Improved signed payload (certificate, ticket) handling.
* Prefer strlen + strcmp over strncmp whenever possible.
* Simplify header file inclusions in source files.
* Simplify background gamecard thread logic.
* Properly close keys file handle if there's a key parse error.
* Update NcaKeyGeneration enum.
* Small changes to save.c/h.
Will probably have to revert some USB changes...
