kernel_efivars: fix check for fedora
kernel_efivars: fix check for fedora

For some weird reason, mount -l -t efivarfs is illegal on fedora.  Just do
mount -l and grep for efivarfs.

marineam/efitools,mjg59/efitools,mjg59/efitools,marineam/efitools,mjg59/efitools,marineam/efitools,msekletar/efitools,marineam/efitools,msekletar/efitools,msekletar/efitools,msekletar/efitools,mjg59/efitools