Fix host_name and target_name generation by common/create-version.sh.

This new script has one small snafoo, which prevented the $host_alias
and $target_alias from being expanded during the generation of the
version.c file.  As a result, the version info yields:

    This GDB was configured as "--host=$host_alias --target=$target_alias".
                                       ^^^^^^^^^^^          ^^^^^^^^^^^^^

This patch fixes this issue.

gdb/ChangeLog:

        * common/create-version.sh: Fix expansion of $host_alias
        and $target_alias in generation of HOST_NAME and TARGET_NAME
        (resp.).
	* objfiles.h (pc_in_section): New prototype.
	(in_plt_section): Remove name argument, replace prototype with
	static inline function.
	* mips-tdep.h: Include "objfiles.h".
	(in_mips_stubs_section): New function.
	* hppa-tdep.h (gdbarch_tdep): Remove name argument of
	in_solib_call_trampoline member.
	(hppa_in_solib_call_trampoline): Remove name argument.
	* objfiles.c (pc_in_section): New function.
	(in_plt_section): Remove function.
	* mips-linux-tdep.c: Include "objfiles.h".
	(mips_linux_in_dynsym_stub): Call in_mips_stubs_section.  Remove
	name argument.  Return 1 rather than the low 16-bit halfword of
	any instruction examined.
	(mips_linux_in_dynsym_resolve_code): Update
	mips_linux_in_dynsym_stub call accordingly.
	* mips-tdep.c (mips_stub_frame_sniffer): Use in_mips_stubs_section
	rather than an equivalent hand-coded sequence.
	* hppa-hpux-tdep.c (in_opd_section): Remove function.
	(hppa32_hpux_in_solib_call_trampoline): Remove name argument.
	(hppa64_hpux_in_solib_call_trampoline): Likewise.
	(hppa64_hpux_find_global_pointer): Use pc_in_section rather than
	in_opd_section.
	* hppa-tdep.c (hppa_stub_unwind_sniffer): Remove name argument
	on call to tdep->in_solib_call_trampoline.
	(hppa_in_solib_call_trampoline): Remove name argument, update
	according to in_plt_section change.
	(hppa_skip_trampoline_code): Update according to in_plt_section
	change.
	* aarch64-tdep.c (aarch64_stub_unwind_sniffer): Likewise.
	* arm-symbian-tdep.c (arm_symbian_skip_trampoline_code):
	Likewise.
	* arm-tdep.c (arm_stub_unwind_sniffer): Likewise.
	* hppa-linux-tdep.c (hppa_linux_find_global_pointer): Likewise.
	* hppabsd-tdep.c (hppabsd_find_global_pointer): Likewise.
	* nios2-tdep.c (nios2_stub_frame_sniffer): Likewise.
	* nto-tdep.c (nto_relocate_section_addresses): Likewise.
	* s390-tdep.c (s390_stub_frame_sniffer): Likewise.
	* sh-tdep.c (sh_stub_unwind_sniffer): Likewise.
	* solib-dsbt.c (dsbt_in_dynsym_resolve_code): Likewise.
	* solib-frv.c (frv_in_dynsym_resolve_code): Likewise.
	* solib-svr4.c (svr4_in_dynsym_resolve_code): Likewise.
	* solib-target.c (solib_target_in_dynsym_resolve_code): Likewise.
	* sparc-tdep.c (sparc_analyze_prologue): Likewise.
	* tic6x-tdep.c (tic6x_stub_unwind_sniffer): Likewise.