[PATCH] gdb: ignore -Wregister instead of -Wdeprecated-register

[Tom Tromey]

>>>>> "Simon" == Simon Marchi <simon.marchi@efficios.com> writes:

Simon> In ada-lex.l, we already use `DIAGNOSTIC_IGNORE_DEPRECATED_REGISTER`,
Simon> which for Clang translates to ignoring `-Wdeprecated-register` [1].  I think
Simon> that was produced when compiling as C++11, but now that we always compile as
Simon> C++17, Clang produces a `-Wregister` error [2].

Can we just '#define register' in this file or somewhere nearby?

Eventually I'd like to stop using lex for Ada but that's kind of a lot
of work.

Tom