Add tests for HVX disassembly

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The disassembly of HVX instructions is not tested yet.

In order to solve this issue one has to:

1. Add HVX instructions to handwritten/asm-tests/test-code.S which cover all kind of HVX operands (single, double, quartile registers, immediate values).
2. Compile them with the Hexagon SDK, disassemble the binary with the SDKs objdump and compare the disassembly with the one rizin returns.
3. If successful, add the tests here: handwritten/asm-tests/hexagon

Note that the most recent public Hexagon SDK version only supports v62 instructions and previous ones.
But our instruction set also includes instructions until v68.
It would be great if someone finds a way to test those as well.

[Rot127]

Tracked by #27