RFR: JDK 8047933 Race between jdk/make/scripts/genExceptions.sh and com.sun.tools.javadoc.Main

[Tim Bell]

Please review a small change to make/Main.gmk

 https://bugs.openjdk.java.net/browse/JDK-8047933

 http://cr.openjdk.java.net/~tbell/8047933/webrev.00/

Thanks to Erik Joelsson for the suggested fix.

Thanks in advance-

Tim