Aligned internal log buffers on CPUs which require them

The generic buffer structure should respect the alignment of included
log structures. This is required by some CPUs (such as Sparc).

ntfsprogs/ntfsrecover.h

@@ -79,6 +79,7 @@ struct BUFFER {
 	unsigned int headsz;
 	BOOL safe;
 	union {
+		u64 alignment;
 		RESTART_PAGE_HEADER restart;
 		RECORD_PAGE_HEADER record;
 		char data[1];