gdb: Move process_one_symbol to stabsread.c

The function process_one_symbol was defined in the file dbxread.c, but
this function is used by all file formats that handle stabs debug
information. It makes much more sense for it to be in the stabsread.c
file instead.

To move that function, many other static functions had to be moved from
dbxread. A few were only used by process_one_symbol, so they're still
static, but most were used by other functions still in dbxread, so they
are being exported by stabsread.h

Finally, the registry entry has been moved as well, seeing as it was
already exported by gdb-stabs.h, and stabsread.c will need it to
properly use the newly added function.

With this change, reading mdebug files is totally independent of reading
dbx.

Approved-By: Tom Tromey <tom@tromey.com>
4 files changed