x86: Rename VecSIB to SIB for Intel AMX

x86: Rename VecSIB to SIB for Intel AMX

Rename VecSIB to SIB to support Intel Advanced Matrix Extensions which
introduces instructions with a mandatory SIB byte which isn't a vector
SIB (VSIB).

gas/

	* config/tc-i386.c (check_VecOperands): Replace vecsib with sib.
	Replace VecSIB128, VecSIB256 and VecSIB512 with VECSIB128,
	VECSIB256 and VECSIB512, respectively.
	(build_modrm_byte): Replace vecsib with sib.

opcodes/

	* i386-gen.c (opcode_modifiers): Replace VecSIB with SIB.
	(VecSIB128): Renamed to ...
	(VECSIB128): This.
	(VecSIB256): Renamed to ...
	(VECSIB256): This.
	(VecSIB512): Renamed to ...
	(VECSIB512): This.
	(VecSIB): Renamed to ...
	(SIB): This.
	(i386_opcode_modifier): Replace vecsib with sib.
	* i386-opc.tbl (VexSIB128): New.
	(VecSIB256): Likewise.
	(VecSIB512): Likewise.
	Replace VecSIB=1, VecSIB=2 and VecSIB=3 with VexSIB128, VecSIB256
	and VecSIB512, respectively.