Fix format for asm with comments

[straight-shoota]

Fixes a formatter bug that appeared in crystal-lang/crystal-book#746

[HertzDevil]

This still formats that asm expression into:

asm(
  # the assembly template string, following the
  # syntax for LLVM's integrated assembler
  "nop" :               # output operands
 "=r"(foo), "=r"(bar) : # input operands
 "r"(1), "r"(baz) :     # names of clobbered registers
 "eax", "memory" :      # optional flags, corresponding to the LLVM IR
  # sideeffect / alignstack / inteldialect / unwind attributes
 "volatile", "alignstack", "intel", "unwind"
)

The 3 comment lines have the correct indentation, but that's about it. That snippet is supposed to be the correct formatting already, given that defs can do the same.

[straight-shoota]

Argh, should've tested the entire snippet again.

Ouh yeah, there's a hard coded write " " in visit_asm_parts.