ARMv4T (GBA) and ARMv6K (3DS) support (#75)

* Initial ARM support

* Disassemble const pool reloc

* Disasm ARM/Thumb/data based on mapping symbols

* Fallback to mapping symbol `$a`

* Support multiple DWARF sequences

* Update line info

* Rework DWARF line info parsing

- Properly handles multiple sections
  in DWARF 1
- line_info moved into ObjSection
- DWARF 2 parser no longer errors with
  no .text section
- Both parsers properly skip empty
  sections

* Simplify line_info (no Option)

* Get line info from section; output formatted ins string

* Unwrap code section in `arm.rs`

* Handle reloc `R_ARM_SBREL32`

* Update ARM disassembler

* Update README.md

* Format

* Revert "Update README.md"

This reverts commit 8bbfcc6f45.

* Update README.md

* Detect ARM version; support ARMv4T and v6K

* Combobox to force ARM version

* Clear LSB in ARM symbol addresses

* Support big-endian ARM ELF files

* Bump `unarm`, `arm-attr`

* Handle ARM implicit addends

* Update README.md

* Explicitly handle all ARM argument types

* Format

* Display more ARM relocs

* Mask LSB on ARM code symbols only

* Read ARM implicit addends

* Format

---------

Co-authored-by: Luke Street <luke.street@encounterpc.com>

objdiff-core/src/obj/read.rs

@@ -55,12 +55,13 @@ fn to_obj_symbol(
     if obj_file.format() == BinaryFormat::Elf && symbol.scope() == SymbolScope::Linkage {
         flags = ObjSymbolFlagSet(flags.0 | ObjSymbolFlags::Hidden);
     }
+    let address = arch.symbol_address(symbol);
     let section_address = if let Some(section) =
         symbol.section_index().and_then(|idx| obj_file.section_by_index(idx).ok())
     {
-        symbol.address() - section.address()
+        address - section.address()
     } else {
-        symbol.address()
+        address
     };
     let demangled_name = arch.demangle(name);
     // Find the virtual address for the symbol if available
@@ -70,7 +71,7 @@ fn to_obj_symbol(
     Ok(ObjSymbol {
         name: name.to_string(),
         demangled_name,
-        address: symbol.address(),
+        address,
         section_address,
         size: symbol.size(),
         size_known: symbol.size() != 0,