Fix unexpected failures in the linker testsuite for ARM VxWorks targets.

Fix unexpected failures in the linker testsuite for ARM VxWorks targets.

	PR ld/19455
	* elf32-arm.c (elf32_arm_create_dynamic_sections): Set the ELF
	class of the linker stub bfd.
	(elf32_arm_check_relocs): Skip check for pic format after
	processing a vxWorks R_ARM_ABS12 reloc.
	* elflink.c (bfd_elf_final_link): Check for ELFCLASSNONE when
	reporting a class mismatch.

	* testsuite/ld-arm/vxworks1-lib.dd: Update for current
	disassmebler output.
	* testsuite/ld-arm/vxworks1-lib.rd: Likewise.
	* testsuite/ld-arm/vxworks1.dd: Likewise.
	* testsuite/ld-arm/vxworks1.rd: Likewise.
	* testsuite/ld-arm/vxworks1.ld: Set the output format.