On Linux, build SDL2 from externals with HIDAPI support

main: Add running title's version to window name on EA/mainline

Various improvements to IPC and session management

texture_cache: Handle out of bound texture blits

input_common: Implement SDL motion

Fixes the missing title version number on EA/mainline builds which override the title bar string.

externals: Update mbedtls to 8c88150ca

externals: Checkout 79e8d17024 for FFmpeg

6b6b9e593d does not exist on FFmpeg master, and tag n4.3.1 requires
manually fetching all of FFmpeg's tags. `git` reports that the commit
does not exist initially and can be confusing as a result. Instead,
checkout the immediately previous commit from n4.3.1 on their master
branch.

ssl: Stub Import(Client/Server)Pki

configure_ui: Call RequestGameListUpdate when toggling "Show Add-Ons Column"

- Used in JUMP FORCE Deluxe Edition

hid: Improve hardware accuracy of gestures

- Fixes our error checking of names as well.

- Fixes our move handles implementation to actually move objects.
- Simplifies the traditional IPC path.

- This was not actually closing sessions before.

- This allows us to create a new interface each time ConnectToNamedPort is called, removing the assumption that these are static.

kernel: Eliminate variable shadowing