RFR: JDK-8221876:[macOS] JPackage install takes long time

[semyon.sadetsky at oracle.com]

Hello,

bug: https://bugs.openjdk.java.net/browse/JDK-8221876

webrev: http://cr.openjdk.java.net/~ssadetsky/8221876/webrev.00/

The fix eliminate delay in install which is caused by postinstall script 
introduced in 8215241 when it set permissions for large number of files. 
Actually setting permissions to  the installation folder is sufficient.

--Semyon