repacker: override slot for flashing images instead of using bootctrl

Bootctrl is being unreliable during repacking. This overrides the slot
while repacking recovery in boot.

Change-Id: I0a04357af4e5f24591792bcfb27ccbd10b0a813b
diff --git a/partitions.hpp b/partitions.hpp
index 03a603e..0a3fa0a 100755
--- a/partitions.hpp
+++ b/partitions.hpp
@@ -378,6 +378,7 @@
 	bool Flash_Image(string& path, string& filename);                         // Flashes an image to a selected partition from the partition list
 	bool Restore_Partition(struct PartitionSettings *part_settings);          // Restore the partitions based on type
 	TWAtomicInt stop_backup;
+	void Override_Active_Slot(const string& Slot);                            // Override the active slot for repacking
 	void Set_Active_Slot(const string& Slot);                                 // Sets the active slot to A or B
 	string Get_Active_Slot_Suffix();                                          // Returns active slot _a or _b
 	string Get_Active_Slot_Display();                                         // Returns active slot A or B for display purposes