fix: ebx -> ecx (#46)

utils/cpuid_amd64.go

@@ -26,8 +26,8 @@ func init() {
 	_, ecx, _, _ := cpuid(1, 0)
 	X86.HasAES = bitn(ecx, 25)
 
-	_, ebx, _, _ := cpuid(7, 0)
-	X86.HasBMI2 = bitn(ebx, 8)
-	X86.HasADX = bitn(ebx, 19)
-	X86.HasRDSEED = bitn(ebx, 18)
+	_, ecx, _, _ = cpuid(7, 0)
+	X86.HasBMI2 = bitn(ecx, 8)
+	X86.HasADX = bitn(ecx, 19)
+	X86.HasRDSEED = bitn(ecx, 18)
 }