Make mysqld_multi.server executable, and allow it to be installed
via chkconfig on LSB-compliant systems.
scripts/make_binary_distribution.sh:
Adjust permissions on some support-files/* scripts: make mysqld_multi.server
executable, and mysql-VERSION.spec not executable.
support-files/mysqld_multi.server.sh:
Add LSB comments for chkconfig to simplify installation for sysadmins.