libpng: Update to 1.6.15

mingw-w64-libpng/PKGBUILD

@@ -2,7 +2,7 @@
 
 _realname=libpng
 pkgname="${MINGW_PACKAGE_PREFIX}-${_realname}"
-pkgver=1.6.14
+pkgver=1.6.15
 pkgrel=1
 arch=('any')
 pkgdesc="A collection of routines used to create PNG format graphics (mingw-w64)"
@@ -15,8 +15,8 @@ options=('strip' '!libtool' 'staticlibs')
 source=("http://downloads.sourceforge.net/sourceforge/libpng/libpng-$pkgver.tar.xz"
         "http://downloads.sourceforge.net/project/libpng-apng/libpng16/$pkgver/libpng-$pkgver-apng.patch.gz")
 
-md5sums=('aefd9fda2178acab908707737174a0cd'
-         '39f35cde00159c24b5a10258d8f2c5ce')
+md5sums=('a95cb387c53215b034203b41ec57c7e5'
+         '612524080d5515f4ea81541a9b13bf61')
 
 prepare() {
   cd "$srcdir/libpng-$pkgver"