[libpng12] Changed AM_CONFIG_HEADER(config.h) to AC_CONFIG_HEADERS([config.h])

in configure.ac
diff --git a/ANNOUNCE b/ANNOUNCE
index 1e22612..67bab66 100644
--- a/ANNOUNCE
+++ b/ANNOUNCE
@@ -1,5 +1,5 @@
 
-Libpng 1.2.51beta01 - January 1, 2013
+Libpng 1.2.51beta01 - January 3, 2013
 
 This is not intended to be a public release.  It will be replaced
 within a few weeks by a public version or by another test version.
@@ -42,8 +42,10 @@
 
 Changes since the last public release (1.2.50):
 
-version 1.2.51beta01 [January 1, 2013]
+version 1.2.51beta01 [January 3, 2013]
   Ignore, with a warning, out-of-range value of num_trans in png_set_tRNS().
+  Replaced AM_CONFIG_HEADER(config.h) with AC_CONFIG_HEADERS([config.h])
+    in configure.ac
 
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 https://lists.sourceforge.net/lists/listinfo/png-mng-implement
diff --git a/CHANGES b/CHANGES
index 9c5ce6a..79eaf2d 100644
--- a/CHANGES
+++ b/CHANGES
@@ -2777,9 +2777,11 @@
 version 1.0.60 and 1.2.50 [July 9, 2012]
   Changed "a+w" to "u+w" in Makefile.in to fix CVE-2012-3386.
 
-version 1.2.51beta01 [January 1, 2013]
+version 1.2.51beta01 [January 3, 2013]
   Rebuilt the configure scripts with autoconf-2.69
   Ignore, with a warning, out-of-range value of num_trans in png_set_tRNS().
+  Replaced AM_CONFIG_HEADER(config.h) with AC_CONFIG_HEADERS([config.h])
+    in configure.ac
 
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diff --git a/configure.ac b/configure.ac
index 4ac5177..1a4188b 100644
--- a/configure.ac
+++ b/configure.ac
@@ -31,7 +31,7 @@
 dnl End of version number stuff
 
 AC_CONFIG_SRCDIR([pngget.c])
-AM_CONFIG_HEADER(config.h)
+AC_CONFIG_HEADERS([config.h])
 
 # Checks for programs.
 AC_PROG_CC