staging: greybus: tools: fix spelling

Fixed the spelling mistake of appendation to appending.

Signed-off-by: Vaibhav Nagare <vnagare@redhat.com>
Link: https://lore.kernel.org/r/20220425133111.118257-1-vnagare@redhat.com


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>