Update README.md

Author: coder2z

README.md

@@ -74,7 +74,7 @@ func main() {
 				},
 			},
 			Flags: func(c *xflag.Command) {
-				c.Flags().StringP("config", "c", "", "配置文件")
+				c.Flags().StringP("xcfg", "c", "", "配置文件")
 				_ = c.MarkFlagRequired("config")
 			},
 		},
@@ -126,4 +126,4 @@ them, and corrected the errors in the document, please submit a Pull Request~
 
 ## :closed_book:License
 
-Distributed under MIT License, please see license file within the code for more details.
+Distributed under MIT License, please see license file within the code for more details.