* sky-vu.c: new file to read/write VU registers

	* sky-vu.c: new file to read/write VU registers
        * Makefile.in .Sanitize: add sky-vu.c
	* sky-vu.h: define registers as enum, export read/write routines
        * sky-vu[01].[ch]: use register read/write routines in sky-vu.c
        * interp.c: use register read/write routines in sky-vu.c