Update to new binaryninja API and fix some bugs (including #20)

[clark-ja]

As the title says, this PR makes the binja-hexagon architecture plugin compatible to the newest binaryninja API and fixes some bugs.

Changes:

• update binaryninja-api submodule (to latest dev commit)
• update abseil-cpp submodule (to latest LTS)
• add string.h include to third party qemu-hexagon module
• fix the order of children and meta arguments in python functions decorated with lark @v_args(meta=True) decorators (view also Improve documentation of v_args meta option. lark-parser/lark#1302)

Tested and working with Binary Ninja 4.3.6676-dev Personal on Linux

[google-cla]

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[clark-ja]

Oh, and if that is preferred, I can also change the binaryninja-api submodule to the latest stable version instead.

[cfircohen]

Thanks for the fix!

[cfircohen]

Looks like I can no longer push to main, I'll see if I can find a Googler to own this repo.