Replace the remaining uses of PNG_CONST with const
In v1.6.0, compiler support for const became a requirement.
It should be used consistently. To maintain backwards compatibility,
PNG_CONST is still maintained in deprecated form.
diff --git a/pngset.c b/pngset.c
index e90e35a..d1d7354 100644
--- a/pngset.c
+++ b/pngset.c
@@ -1399,7 +1399,7 @@
/* Ignore all unknown chunks and all chunks recognized by
* libpng except for IHDR, PLTE, tRNS, IDAT, and IEND
*/
- static PNG_CONST png_byte chunks_to_ignore[] = {
+ static const png_byte chunks_to_ignore[] = {
98, 75, 71, 68, '\0', /* bKGD */
99, 72, 82, 77, '\0', /* cHRM */
101, 88, 73, 102, '\0', /* eXIf */