sony-tuba: new device

Add new device Sony Xperia XA, code name is sony-tuba.

Building kernel, flashing, ssh through usb and display work. Buttons and a lot of other things do not work.

Tested with the single sim model F3111, but the expectation that also dual sim can be made to work using the same package.

The correct source for the vendor kernel is Sony Developer World. Unfortunately, the kernel for this particular model does not seem to be available in their Git repositories. Zip archives do have kernel sources, but not for the most recent build 33.3.A.1.126. .115 seems to be the latest that is available. A request to make the latest build available has been sent to Sony, but no response has been received. In the mean time, third party SonyCustoms repository looks like it has the correct content and is used here.

Vendor kernel build included running a tool called DrvGen which emits the device tree config cust.dtsi. Unfortunately, running the tool as part of postmarketOS build is quite challenging, as it has been built against glibc and, being both a gui and a cli tool at the same time, depends on some graphical libraries as well. Following the precedent set by kernel-wiko-lenny3 package, a patch is applied to disable running the tool and add the generation result to source tree.

EDIT: Added a new commit after quite a lot of review had already taken place. Adding package msm-fb-refresher fixed nonresponsiveness issue with the screen and allowed to confirm that the touchscreen works.