Implement ARM unwind opcode assembler.
[WORK IN PROGRESS] Add a tool to dump ARM unwind opcodes.
Split unwind opcode assembler.
Use meaningful constant name.
Enhance test case for ARM EH section with user-defined section name.
Refine the assembler.
Refine __aeabi_unwind_cpp_pr.
Add more message for assertion.
Refine the code for personality index and buffer reservation.
Change the condition.
Rename AEABI_CPP_UNWIND_CPP_PR to AEABI_UNWIND_CPP_PR.

To make it closer to __aeabi_unwind_cpp_pr0.
Rename INVALID_PERSONALITY_INDEX.
Rename MAX_PERSONALITY_INDEX to NUM_PERSONALITY_INDEX.
Add comments.
Rename missing opcode.
Fix test cases.