[llvm-objdump] Add --no-print-imm-hex to the command guide

[gbreynoo]

Summary

The option --no-print-imm-hex was not included in the command guide for llvm-objdump but appears in the help text. This commit adds it to the command guide.

[MaskRay]

I am on the fence. For certain boolean options, I think it is usually sufficient to document just the non-default option (e.g. --foo), no need for the default option (e.g. --no-foo).

[keith]

I think these are nice to document since sometimes it's useful to be able to negate the previous passed flag, especially if you're doing it in some sort of script, but I have to admit I've never had that case with llvm-objdump

[jhenderson]

In D104717#2833469, @MaskRay wrote:

I am on the fence. For certain boolean options, I think it is usually sufficient to document just the non-default option (e.g. --foo), no need for the default option (e.g. --no-foo).

I don't think it is necessarily obvious which options can be negated. Certainly, for some options in some tools, there is no --no-* equivalent.

LGTM.

llvm/docs/CommandGuide/llvm-objdump.rst

 .. option:: --mattr=<a1,+a2,-a3,...>
 
   Enable/disable target-specific attributes. Specify ``--mattr=help`` to display
   the available attributes.
 
 .. option:: --no-leading-addr
 
   When disassembling, do not print leading addresses.
   
+.. option:: --no-print-imm-hex
+
+  Do not use hex format for immediate values in disassembly output (default).
+
 .. option:: --no-show-raw-insn
 
   When disassembling, do not print the raw bytes of each instruction.
 
 .. option:: --prefix=<prefix>
 
   When disassembling with the :option:`--source` option, prepend ``prefix`` to
   absolute paths.