uek-rpm: Clean up installed directories when uninstalling kernel-ueknano

uek-rpm: Clean up installed directories when uninstalling kernel-ueknano

Orabug: 26929773

When creating kernel-ueknano package, the files (modules) to be included in
it are supplied from a input file. This input file lists the modules with
install path. When installing the rpm, parent directories for these
files are created automatically. When uninstalling, the modules get removed
but not the parent directories.  Because of this, /lib/modules/<kversion>/kernel
and its subdirectories are left intact even after the package uninstall.

This commit adds post uninstall scriptlet to remove the
"/lib/modules/<kversion>/" directory when the package is uninstalled.

Signed-off-by: Somasundaram Krishnasamy <somasundaram.krishnasamy@oracle.com>
Reviewed-by: Jack Vogel <jack.vogel@oracle.com>