Revert preference to be an int.

While in base we use it as a boolean (of the wrong spelling), there's
at least one out of tree user that needs it to be int since priorirty
is a small int, not a 0/1. In deference to the time it's wasted me and
my team, push this up into FreeBSD for whatever short life boot1 may
have in the tree.

stand/efi/boot1/boot_module.h

@@ -51,7 +51,7 @@ typedef struct dev_info
 	EFI_HANDLE *devhandle;
 	void *devdata;
 	uint64_t partoff;
-	BOOLEAN preferred;
+	int preferred;
 	struct dev_info *next;
 } dev_info_t;