simple_file: fix bug in path and file concatenation
simple_file: fix bug in path and file concatenation

The current simple file doesn't add a backslash between the path and the file
meaning it only works if everything is in the top level directory.  Fix by
adding the separator

Signed-off-by: James Bottomley <1acebbdca565c7b6b638bdc23b58b5610d1a56b8@Parallels.com>

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