用独立的钥匙链存储设备信息，避免冲突。review by 海哥。

@@ -68,6 +68,8 @@ static NSString * const kOpenUDIDSlotPBPrefix = @"org.OpenUDID.slot.";
 static int const kOpenUDIDRedundancySlots = 100;
 static NSString * const kYohoSecretInfo = @"com.yoho.buy.secretinfo";
 static NSString * const kYohoBuyUdid = @"com.yoho.buy.udid";
+
+static NSString * const kYohoDeviceInfo = @"com.yoho.buy.deviceinfo";
 static NSString * const kYohoBuyUsedDevice = @"com.yoho.buy.useddevice";
 
 @interface OpenUDID (Private)
@@ -395,14 +397,14 @@ static NSString * const kYohoBuyUsedDevice = @"com.yoho.buy.useddevice";
 
 + (void) setUsedDevice
 {
-    NSMutableDictionary *yohoinfoKVPairs = (NSMutableDictionary *)[YH_KeychainStore load:kYohoSecretInfo];
+    NSMutableDictionary *yohoinfoKVPairs = (NSMutableDictionary *)[YH_KeychainStore load:kYohoDeviceInfo];
     if (yohoinfoKVPairs == nil) {
         yohoinfoKVPairs = [NSMutableDictionary dictionary];
     }
     
     if (![yohoinfoKVPairs[kYohoBuyUsedDevice] isEqualToString:@"Y"]) {
         [yohoinfoKVPairs setObject:@"Y" forKey:kYohoBuyUsedDevice];
-        [YH_KeychainStore save:kYohoSecretInfo data:yohoinfoKVPairs];
+        [YH_KeychainStore save:kYohoDeviceInfo data:yohoinfoKVPairs];
     }
 }
 
@@ -413,7 +415,7 @@ static NSString * const kYohoBuyUsedDevice = @"com.yoho.buy.useddevice";
         return NO;
     }
     
-    NSMutableDictionary *yohoinfoKVPairs = (NSMutableDictionary *)[YH_KeychainStore load:kYohoSecretInfo];
+    NSMutableDictionary *yohoinfoKVPairs = (NSMutableDictionary *)[YH_KeychainStore load:kYohoDeviceInfo];
     if (yohoinfoKVPairs == nil || yohoinfoKVPairs[kYohoBuyUsedDevice] == nil) {
         return YES;
     } else {