fix zlib source path in patch file

remove-ub-in-zlib.patch

@@ -17,8 +17,8 @@ to avoid the possibility of undefined behavior.
 
 diff --git a/inftrees.c b/inftrees.c
 index 22fcd6666..0d2670d57 100644
---- a/inftrees.c
-+++ b/inftrees.c
+--- a/zlib/inftrees.c
++++ b/zlib/inftrees.c
 @@ -54,7 +54,7 @@ unsigned short FAR *work;
      code FAR *next;             /* next available space in table */
      const unsigned short FAR *base;     /* base value table to use */