Support i386 TLS code sequences without PLT

Support i386 TLS code sequences without PLT

We can generate i386 TLS code sequences for general and local dynamic
models without PLT, which uses indirect call via GOT:

call *___tls_get_addr@GOT(%reg)

where EBX register isn't required as GOT base, instead of direct call:

call ___tls_get_addr[@PLT]

which requires EBX register as GOT base.

Since direct call is 4-byte long and indirect call, is 5-byte long, the
extra one byte must be handled properly.

For general dynamic model, 7-byte lea instruction before call instruction
is replaced by 6-byte one to make room for indirect call.  For local
dynamic model, we simply use 5-byte indirect call.

TLS linker optimization is updated to recognize new instruction patterns.
For local dynamic model to local exec model transition, we generate
a 6-byte lea instruction as nop, instead of a 1-byte nop plus a 4-byte
lea instruction.  Since linker may convert

call ___tls_get_addr[@PLT]

to

addr32 call ____tls_get_addr

when producing static executable, both patterns are recognized.

bfd/

	* elf64-i386.c (elf_i386_link_hash_entry): Add tls_get_addr.
	(elf_i386_link_hash_newfunc): Initialize tls_get_addr to 2.
	(elf_i386_check_tls_transition): Check indirect call and direct
	call with the addr32 prefix for general and local dynamic models.
	Set the tls_get_addr feild.
	(elf_i386_convert_load_reloc): Always use addr32 prefix for
	indirect ___tls_get_addr call via GOT.
	(elf_i386_relocate_section): Handle GD->LE, GD->IE and LD->LE
	transitions with indirect call and direct call with the addr32
	prefix.

ld/

	* testsuite/ld-i386/i386.exp: Run libtlspic2.so, tlsbin2,
	tlsgd3, tlsld2, tlsgd4, tlspie3a, tlspie3b and tlspie3c.
	* testsuite/ld-i386/pass.out: New file.
	* testsuite/ld-i386/tls-def1.c: Likewise.
	* testsuite/ld-i386/tls-gd1.S: Likewise.
	* testsuite/ld-i386/tls-ld1.S: Likewise.
	* testsuite/ld-i386/tls-main1.c: Likewise.
	* testsuite/ld-i386/tls.exp: Likewise.
	* testsuite/ld-i386/tlsbin2-nacl.rd: Likewise.
	* testsuite/ld-i386/tlsbin2.dd: Likewise.
	* testsuite/ld-i386/tlsbin2.rd: Likewise.
	* testsuite/ld-i386/tlsbin2.sd: Likewise.
	* testsuite/ld-i386/tlsbin2.td: Likewise.
	* testsuite/ld-i386/tlsbinpic2.s: Likewise.
	* testsuite/ld-i386/tlsgd3.dd: Likewise.
	* testsuite/ld-i386/tlsgd3.s: Likewise.
	* testsuite/ld-i386/tlsgd4.d: Likewise.
	* testsuite/ld-i386/tlsgd4.s: Likewise.
	* testsuite/ld-i386/tlsld2.s: Likewise.
	* testsuite/ld-i386/tlspic2-nacl.rd: Likewise.
	* testsuite/ld-i386/tlspic2.dd: Likewise.
	* testsuite/ld-i386/tlspic2.rd: Likewise.
	* testsuite/ld-i386/tlspic2.sd: Likewise.
	* testsuite/ld-i386/tlspic2.td: Likewise.
	* testsuite/ld-i386/tlspic3.s: Likewise.
	* testsuite/ld-i386/tlspie3.s: Likewise.
	* testsuite/ld-i386/tlspie3a.d: Likewise.
	* testsuite/ld-i386/tlspie3b.d: Likewise.
	* testsuite/ld-i386/tlspie3c.d: Likewise.