add cpuid instruction

Reference: /n/atom/patch/applied2013/cpuid8a
Date: Tue Jun 18 20:48:34 CES 2013
Signed-off-by: quanstro@quanstro.net

--- /sys/src/cmd/8a/lex.c	Tue Jun 18 20:48:30 2013
+++ /sys/src/cmd/8a/lex.c	Tue Jun 18 20:48:30 2013
@@ -297,6 +297,7 @@
 	"CMPXCHGB",	LTYPE3,	ACMPXCHGB,
 	"CMPXCHGL",	LTYPE3,	ACMPXCHGL,
 	"CMPXCHGW",	LTYPE3,	ACMPXCHGW,
+	"CPUID",	LTYPE0,	ACPUID,
 	"DAA",		LTYPE0,	ADAA,
 	"DAS",		LTYPE0,	ADAS,
 	"DATA",		LTYPED,	ADATA,