i386: Add and use one_operand_p to vec_perm control struct.

	* config/i386/i386.c (struct expand_vec_perm_d): Add one_operand_p.
	(ix86_expand_vector_init_duplicate): Initialize it.
	(expand_vec_perm_palignr): Likewise.
	(ix86_expand_vec_perm_const): Likewise.
	(ix86_vectorize_vec_perm_const_ok): Likewise.
	(expand_vec_perm_blend): Use it.
	(expand_vec_perm_vpermil): Likewise.
	(expand_vec_perm_pshufb): Likewise.
	(expand_vec_perm_1): Likewise.
	(expand_vec_perm_pshuflw_pshufhw): Likewise.
	(expand_vec_perm_interleave2): Likewise.
	(expand_vec_perm_vpermq_perm_1): Likewise.
	(expand_vec_perm_vperm2f128): Likewise.
	(expand_vec_perm_interleave3): Likewise.
	(expand_vec_perm_vperm2f128_vblend): Likewise.
	(expand_vec_perm_vpshufb2_vpermq): Likewise.
	(expand_vec_perm_vpshufb2_vpermq_even_odd): Likewise,.
	(expand_vec_perm_broadcast): Likewise.
	(expand_vec_perm_vpshufb4_vpermq2): Likewise.

From-SVN: r186017