nm/objdump --hep still display unsupported styles about --demangle.

[nora-pxh]

Hello, I find a problem about usage.

The commit 1910070b298052d7ca8e4024891465824588c1e9 fixed demangle.h to

remove support for ancient GNU (pre-3.0), Lucid, ARM, HP, and EDG demangling styles.

But usage of nm and objdump is still show the following message.

  -C, --demangle[=STYLE] Decode low-level symbol names into user-level names

                          The STYLE, if specified, can be `auto' (the default),

                          `gnu', `lucid', `arm', `hp', `edg', `gnu-v3', `java'

                          or `gnat'

So  if you execute --demangle=gnu, it will display error message: unknown demangling style gnu. 

Would you delete unsupported  styles from usage of nm and objdump?