Fix minor typo in zlib.h comments [RzeĊniowiecki].
diff --git a/zlib.h b/zlib.h
index 3d3ab71..db47bf8 100644
--- a/zlib.h
+++ b/zlib.h
@@ -1578,9 +1578,8 @@
/*
Update a running CRC-32 with the bytes buf[0..len-1] and return the
updated CRC-32. If buf is Z_NULL, this function returns the required
- initial value for the for the crc. Pre- and post-conditioning (one's
- complement) is performed within this function so it shouldn't be done by the
- application.
+ initial value for the crc. Pre- and post-conditioning (one's complement) is
+ performed within this function so it shouldn't be done by the application.
Usage example: