symtab-reader: Setup aliases before checking ppc64 opd function entries

symtab-reader: Setup aliases before checking ppc64 opd function entries

The update_function_entry_address_symbol_map function checks whether
the given symbol is an alias of another symbol or a special ppc64
ELFv1 function entry symbol. This requires the symbol aliases to
already been setup. But the alias entries were only setup after
calling update_function_entry_address_symbol_map. Make sure that the
symbol aliases have been setup and only then call the special ppc64
update_function_entry_address_symbol_map function. But make sure the
arm32 function symbol entry address cleanup is done before checking
for aliases.

This patch renames symtab::get_symbol_value into
symtab::setup_symbol_lookup_tables to better reflect what it does.

It is in that function that the call to
update_function_entry_address_symbol_map is performed, the arm32
symbol address cleanup is done and the ppc64 ELFv1 function address
plumbing is done.

So arranging for update_function_entry_address_symbol_map to be called
after symbol aliases are setup for ppc64 is also done in that
function.  That way, symtab::load_ only have to call
symtab::setup_symbol_lookup_tables to have aliases setup.

This fixes runtestslowselfcompare.sh on ppc64 (ELFv1) with
ENABLE_SLOW_TEST=yes

	* src/abg-elf-helpers.h (architecture_is_ppc32): Declare new
	function.
	* src/abg-elf-helpers.cc (architecture_is_ppc32): Define it.
	* src/abg-symtab-reader.cc
	(symtab::setup_symbol_lookup_tables): Rename
	symtab::get_symbol_value into this. Setup symbol aliases before
	setting up function entry address maps for ppc{32,64} ELFv1 and
	after fixing up arm32/64 addresses.
	(symtab::load_): Invoke the new setup_symbol_lookup_tables.
	update_function_entry_address_symbol_map after setting up aliases.
	No need to setup symbol aliases anymore.
	(symtab::add_alternative_address_lookups): Invoke the new
	setup_symbol_lookup_tables.

Signed-off-by: Mark Wielaard <mark@klomp.org>
Signed-off-by: Dodji Seketeli <dodji@redhat.com>