[llvm-objdump] Decrease instruction indentation for non-x86
Place the instruction at the 24th column (0-based indexing), matching
GNU objdump ARM/AArch64/powerpc/etc when the address is low.
This is beneficial for non-x86 targets which have short instruction
lengths.
```
// GNU objdump AArch64
0:
91001062 add x2, x3, #0x4
400078:
91001062 add x2, x3, #0x4
// llvm-objdump, with this patch
0: 62 10 00 91 add x2, x3, #4
400078: 62 10 00 91 add x2, x3, #4
// llvm-objdump, if we change to print a word instead of bytes in the future
0:
91001062 add x2, x3, #4
400078:
91001062 add x2, x3, #4
// GNU objdump Thumb
0: bf00 nop
// GNU objdump Power ISA 3.1 64-bit instruction
// 0: 00 00 10 04 plwa r3,0
// 4: 00 00 60 a4
```
Reviewed By: jhenderson
Differential Revision: https://reviews.llvm.org/D81590