Remove duplicate code.

scripts/wsrep_sst_mysqldump.sh

@@ -76,17 +76,6 @@ fi
 # word, it is arguably more secure than passing password on the command line.
 [ -n "$WSREP_SST_OPT_PSWD" ] && export MYSQL_PWD="$WSREP_SST_OPT_PSWD"
 
-# Refs https://github.com/codership/mysql-wsrep/issues/141
-# Passing password in MYSQL_PWD environment variable is considered
-# "extremely insecure" by MySQL Guidelines for Password Security
-# (https://dev.mysql.com/doc/refman/5.6/en/password-security-user.html)
-# that is even less secure than passing it on a command line! It is doubtful:
-# the whole command line is easily observable by any unprivileged user via ps,
-# whereas (at least on Linux) unprivileged user can't see process environment
-# that he does not own. So while it may be not secure in the NSA sense of the
-# word, it is arguably more secure than passing password on the command line.
-[ -n "$WSREP_SST_OPT_PSWD" ] && export MYSQL_PWD="$WSREP_SST_OPT_PSWD"
-
 STOP_WSREP="SET wsrep_on=OFF;"
 
 # mysqldump cannot restore CSV tables, fix this issue