m/p/efivarfs: BootOrder fixes

This doesn't need to be a pointer as it's a slice.
There was also a bug left in here because it previously skipped over
the attributes field which we now treat separately.

Change-Id: Icc80496e9bc826ae11201f96a703fb80f97c478a
Reviewed-on: https://review.monogon.dev/c/monogon/+/1913
Tested-by: Jenkins CI
Reviewed-by: Serge Bazanski <serge@monogon.tech>
diff --git a/metropolis/pkg/efivarfs/variables.go b/metropolis/pkg/efivarfs/variables.go
index 876173c..3f435bf 100644
--- a/metropolis/pkg/efivarfs/variables.go
+++ b/metropolis/pkg/efivarfs/variables.go
@@ -110,12 +110,12 @@
 
 // SetBootOrder replaces contents of the boot order variable with the order
 // specified in ord.
-func SetBootOrder(ord *BootOrder) error {
+func SetBootOrder(ord BootOrder) error {
 	return Write(ScopeGlobal, "BootOrder", AttrNonVolatile|AttrRuntimeAccess, ord.Marshal())
 }
 
 // GetBootOrder returns the current boot order of the system.
-func GetBootOrder() (*BootOrder, error) {
+func GetBootOrder() (BootOrder, error) {
 	raw, _, err := Read(ScopeGlobal, "BootOrder")
 	if err != nil {
 		return nil, err