[pam-ipmi]: fix default data file permissions

Use install-data-hook to set correct permissions on the data files. The
default data file is installed as 0644, and these two files need 0600.

Tested: checked that the files get installed as 0600

Change-Id: Ie93104f5f6c8df6903c8b52b276af3f217f54263
Signed-off-by: Vernon Mauery <vernon.mauery@linux.intel.com>
1 file changed