Target FP: Remove convert_typed_floating from tdep files

Target FP: Remove convert_typed_floating from tdep files

This patch mechanically replaces convert_typed_floating with the
equivalent target_float_convert throughout tdep files, to prepare
for the removal of doublest.{c,h}.

No functional change intended.

gdb/ChangeLog:
2017-11-06  Ulrich Weigand  <uweigand@de.ibm.com>

	* i386-tdep.c: Include "target-float.h".  Do not include "doublest.h".
	(i386_extract_return_value): Use target_float_convert.
	(i386_store_return_value): Likewise.
	* i387-tdep.c (i387_register_to_value): Use target_float_convert.
	(i387_value_to_register): Likewise.
	* ia64-tdep.c: Include "target-float.h".  Do not include "doublest.h".
	(ia64_register_to_value): Use target_float_convert.
	(ia64_value_to_register): Likewise.
	(ia64_extract_return_value): Likewise.
	(ia64_store_return_value): Likewise.
	(ia64_push_dummy_call): Likewise.
	* m68k-tdep.c: Include "target-float.h".
	(m68k_register_to_value): Use target_float_convert.
	(m68k_value_to_register): Likewise.
	(m68k_svr4_extract_return_value): Likewise.
	(m68k_svr4_store_return_value): Likewise.
	* ppc-sysv-tdep.c: Include "target-float.h".
	(ppc_sysv_abi_push_dummy_call): Use target_float_convert.
	(do_ppc_sysv_return_value): Likewise.
	(ppc64_sysv_abi_push_freg): Likewise.
	(ppc64_sysv_abi_return_value_base): Likewise.
	* rs6000-aix-tdep.c: Include "target-float.h".
	(rs6000_push_dummy_call): Use target_float_convert.
	(rs6000_return_value): Likewise.
	* rs6000-lynx178-tdep.c: Include "target-float.h".
	(rs6000_lynx178_push_dummy_call): Use target_float_convert.
	(rs6000_lynx178_return_value): Likewise.
	* rs6000-tdep.c: Include "target-float.h".  Do not include "doublest.h".
	(rs6000_register_to_value): Use target_float_convert.
	(rs6000_value_to_register): Likewise.
	* arm-tdep.c: Include "target-float.h".  Do not include "doublest.h".
	(arm_extract_return_value): Use target_float_convert.
	(arm_store_return_value): Likewise.
	* sh-tdep.c: Include "target-float.h".  Do not include "doublest.h".
	(sh_register_convert_to_virtual): Use target_float_convert.
	(sh_register_convert_to_raw): Likewise.
	* sh64-tdep.c: Include "target-float.h".
	(sh64_extract_return_value): Use target_float_convert.
	(sh64_register_convert_to_virtual): Likewise.
	(sh64_register_convert_to_raw): Likewise.  Fix argument types.