Use objcopy to build ramdisk object

. during build, uses much less memory,
	  disk space, and time
	. lets us throw out bintoc

drivers/memory/local.h

@@ -2,5 +2,8 @@
 local defines and declarations 
 */
 
-extern unsigned char imgrd[];
-extern size_t imgrd_size;
+extern unsigned char _binary_imgrd_mfs_start[], *_binary_imgrd_mfs_end;
+
+#define	imgrd	_binary_imgrd_mfs_start
+#define	imgrd_size \
+	((size_t)(_binary_imgrd_mfs_end - _binary_imgrd_mfs_start))