unlzo: fix input buffer free

unlzo modifies the pointer to in_buf, so we have to free the original
buffer, not the modified pointer.

Signed-off-by: Sascha Hauer <s.hauer@xxxxxxxxxxxxxx>
Signed-off-by: Jan Beulich <jbeulich@xxxxxxxx>

--- a/xen/common/unlzo.c
+++ b/xen/common/unlzo.c
@@ -254,7 +254,7 @@ STATIC int INIT unlzo(u8 *input, unsigne
 	ret = 0;
 exit_2:
 	if (!input)
-		free(in_buf);
+		free(in_buf_save);
 exit_1:
 	if (!output)
 		free(out_buf);