[Bug libgcc/78064] unwind-c.c never uses _Unwind_GetIPInfo

[wilson at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=78064

--- Comment #2 from Jim Wilson <wilson at gcc dot gnu.org> ---
The old configure.ac before the patch breaks this has
 GCC_TARGET_TEMPLATE(HAVE_GETIPINFO)
which prevents the ifndef/endif from being added to config.in.  But this
apparently only works in the gcc dir, and I don't think it can be used after
the changes made by the patch as the configure check moved into the
config/unwind_ipinfo.m4 file.  Including auto-target.h seems to be the simpler
fix.