* ldexp.c, ldlang.c, ldmain.c, ldsym.c, ldwarn.c: Use new

	* ldexp.c, ldlang.c, ldmain.c, ldsym.c, ldwarn.c:  Use new
	macro bfd_asymbol_bfd as appropriate.
	* Makefile.in:  Un-duplicate ldlex.c dependency.
	* condigure.in:  Replace my_host case table by sourcing
	../bfd/configure.host.  Allow std-host as the default.
	* ldmisc.c:  Change logic for C++ name demangling:  There is
	no initial '_' to remove from stab-derived function names.