sys: Preserve permissions and preserve symlinks when copying

copy_all() is already doing that and this is important if we try to
use copy() for any file in the system root.

Signed-off-by: Otavio Pontes <otavio.pontes@intel.com>

src/lib/sys.c

@@ -227,7 +227,7 @@ int copy_all(const char *src, const char *dst)
 
 int copy(const char *src, const char *dst)
 {
-	return run_command_quiet("/bin/cp", src, dst, NULL);
+	return run_command_quiet("/bin/cp", "--preserve=all", "--no-dereference", src, dst, NULL);
 }
 
 int mkdir_p(const char *dir)