Fix compile time warnings generated when compiling with clang.

bfd	* bout.c (b_out_slurp_reloc_table): Cast constant to unsigned in
	order to avoid problems with left shifting negative values.
	(abs32code): Likewise.
	* mach-o.c (FILE_ALIGN): Likewise.
	* coff-rs6000.c (xcoff_debug_sections): Delete unused static
	array.
	* elf32-visium.c (visium_reloc_map): Likewise.
	* elf32-arm.c (elf32_arm_final_link_relocate): Remove useless
	calls to abs function.
	* elf32-frv.c (_frvfdpic_relax_tls_entries): Likewise.
	* elf32-score.c (score_elf_final_link_relocate): Likewise.
	* elf32-score7.c (score_elf_final_link_relocate): Likewise.
	* elf32-i860.c (i860_howto_pc26_reloc): Use multiplication instead
	of shifting to create a negative mask.
	* elf32-msp430.c (elf_backend_special_sections): Define.
	* elfxx-mips.c (got_ofst_reloc_p): Delete unused function.
	(got_hi16_reloc_p): Delete unused function.
	* ppcboot.c (ppcboot_bfd_print_private_bfd_data): Fix test of
	partition name.

gas	* config/tc-ppc.c (insn_validate): Cast PPC_OPSHIFT_INV to an int.

opcode	* ppc.h (PPC_OPSHIFT_INV): Use an unsigned constant when left
	shifting.

ld	* emultempl/elf32.em (ehdr_start_empty): New static variable.
	(before_allocation): Use it to initialise ehdr_start_save.
	* emultempl/pe.em (write_build_id): Remove useless double
	parenthesis.
	* emultempl/pep.em (write_build_id): Likewise.

opcodes	* bfin-dis.c (fmtconst): Remove unnecessary call to the abs
	function.
	* tic30-dis.c (print_branch): Likewise.
	* cgen-asm.c (cgen_parse_signed_integer): Cast integer to signed
	value before left shifting.
	* fr30-ibld.c (fr30_cgen_extract_operand): Likewise.
	* hppa-dis.c (print_insn_hppa): Likewise.
	* mips-dis.c (mips_cp0sel_names_mipsr5900): Delete unused static
	array.
	* msp430-dis.c (msp430_singleoperand): Likewise.
	(msp430_doubleoperand): Likewise.
	(print_insn_msp430): Likewise.
	* nds32-asm.c (parse_operand): Likewise.
	* sh-opc.h (MASK): Likewise.
	* v850-dis.c (get_operand_value): Likewise.