Add JMP32 class to disassembler

[Alan-Jowett]

This pull request primarily focuses on enhancing the ubpf/disassembler.py script with support for 32-bit jumps in the eBPF bytecode disassembly process. The changes include the addition of a new opcode and class for 32-bit jumps, and an update to the disassemble_one function to handle the new opcode and class.

Here are the key changes:

• ubpf/disassembler.py: Added a new opcode jmp32 to the JMP_OPCODES dictionary, which maps opcodes to their string names.
• ubpf/disassembler.py: Introduced a new class BPF_CLASS_JMP32 with a value of 6, representing the class for 32-bit jumps.
• ubpf/disassembler.py: Updated the disassemble_one function to handle the new BPF_CLASS_JMP32 class. It now checks if the class is BPF_CLASS_JMP32 and if so, it retrieves the opcode name and appends "32" to it, indicating a 32-bit jump. The function then proceeds to disassemble the bytecode instruction accordingly.

[coveralls]

coverage: 81.235%. remained the same
when pulling 36f1517 on Alan-Jowett:update_unassembler
into 5d4d78d on iovisor:main.