Fix minor formatting bugs.

Signed-off-by: Peter Jones <pjones@redhat.com>
Clean up "vars" implementation just a little.

Change "/sys/firmware/efi/vars/" to a VARS_PATH macro and use it.

Signed-off-by: Peter Jones <pjones@redhat.com>
Add efi_get_next_variable_name()

The semantics are simple.  Return value of 0 means "done", 1 means
"continue", -1 is error.  Call it over and over and it'll pass back a
pointer to a name and a pointer to a guid.  Do not overwrite these.

Signed-off-by: Peter Jones <pjones@redhat.com>
Make dep generation work a bit better.

Signed-off-by: Peter Jones <pjones@redhat.com>
API change, so bump version to 0.4

Signed-off-by: Peter Jones <pjones@redhat.com>