tic4x disassembly static variables

tic4x disassembly static variables

tic4x uses a number of static variables for tables that are generated
depending on the current machine (tic4x vs. tic3x).  However, it is
possible to change the machine from one invocation of print_insn_tic4x
to the next.  This patch throws away the old state if that happens,
and uses a relatively small known size array of register names rather
than a malloc'd table.

	* tic4x-dis.c (tic4x_version): Make unsigned long.
	(optab, optab_special, registernames): New file scope vars.
	(tic4x_print_register): Set up registernames rather than
	malloc'd registertable.
	(tic4x_disassemble): Delete optable and optable_special.  Use
	optab and optab_special instead.  Throw away old optab,
	optab_special and registernames when info->mach changes.