Add missing s9 CPU. (#364)

Co-authored-by: Zandor Smith <info@zsinfo.nl>

Source/Device.generated.swift

@@ -2137,6 +2137,7 @@ extension Device {
     case s6
     case s7
     case s8
+    case s9
   #endif
     case unknown
   }
@@ -2309,6 +2310,7 @@ extension Device.CPU: CustomStringConvertible {
       case .s6: return "S6"
       case .s7: return "S7"
       case .s8: return "S8"
+      case .s9: return "S9"
       case .unknown: return "unknown"
     }
   #endif

Source/Device.swift.gyb

@@ -1386,6 +1386,7 @@ watchOS_cpus = [
           CPU("s6", "S6"),
           CPU("s7", "S7"),
           CPU("s8", "S8"),
+          CPU("s9", "S9"),
 ]
 }%