Fix the errors 'observer -h' and 'observer -V'

src/observer/main.cpp

@@ -59,7 +59,7 @@ static void print_help()
 {
   MPRINT("observer [OPTIONS]");
   MPRINT("  -h,--help                print this help");
-  MPRINT("  -v,--version             print the information of version");
+  MPRINT("  -V,--version             print the information of version");
   MPRINT("  -z,--zone ZONE           zone");
   MPRINT("  -p,--mysql_port PORT     mysql port");
   MPRINT("  -P,--rpc_port PORT       rpc port");
@@ -158,7 +158,7 @@ static void get_opts_setting(struct option long_opts[], char short_opts[], const
       {"rs_list", 'r', 1},
       {"mode", 'm', 1},
       {"scn", 'f', 1},
-      {"version", 'v', 0},
+      {"version", 'V', 0},
       {"ipv6", '6', 0},
   };