inventory: Kill inventory.img file in case of failed dump

This will result in more sane error in case restore is launched
on such semi-complete images.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

cr-dump.c

@@ -1600,9 +1600,10 @@ err:
 
 	close_safe(&pidns_proc);
 
-	if (ret)
+	if (ret) {
+		kill_inventory();
 		pr_err("Dumping FAILED.\n");
-	else
+	} else
 		pr_info("Dumping finished successfully\n");
 
 	return ret;

image.c

@@ -86,6 +86,12 @@ int write_img_inventory(void)
 	return 0;
 }
 
+void kill_inventory(void)
+{
+	unlinkat(get_service_fd(IMG_FD_OFF),
+			fdset_template[CR_FD_INVENTORY].fmt, 0);
+}
+
 static void show_inventory(int fd, struct cr_options *o)
 {
 	pb_show_vertical(fd, PB_INVENTORY);

include/crtools.h

@@ -179,6 +179,7 @@ void show_rlimit(int fd, struct cr_options *o);
 
 int check_img_inventory(void);
 int write_img_inventory(void);
+void kill_inventory(void);
 
 extern void print_data(unsigned long addr, unsigned char *data, size_t size);
 extern void print_image_data(int fd, unsigned int length, int show);