sysutils/pesign: unbreak on 11.1+

In file included from pesign.h:30:0,

from pesign.c:35:

efitypes.h:50:0: error: "EFI_VARIABLE_NON_VOLATILE" redefined [-Werror]
#define EFI_VARIABLE_NON_VOLATILE 0x0000000000000001
^
In file included from efitypes.h:22:0,

from pesign.h:30,
from pesign.c:35:

/usr/include/efivar.h:38:0: note: this is the location of the previous definition
#define EFI_VARIABLE_NON_VOLATILE 0x00000001
^

Reported by: pkg-fallout