libpng: bump to 1.6.35

Also use https instead of http to retrieve the hashes.

Note that the only changes in the LICENSE file is the copy-right date and
the version number.

Signed-off-by: Nasser Afshin <afshin.nasser@gmail.com>
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>

package/libpng/libpng.hash

@@ -1,7 +1,7 @@
-# From http://sourceforge.net/projects/libpng/files/libpng16/1.6.34/
-md5		c05b6ca7190a5e387b78657dbe5536b2			libpng-1.6.34.tar.xz
-sha1	45de4ec996ffcc3e18037e7c128abe95f4d0292a	libpng-1.6.34.tar.xz
+# From https://sourceforge.net/projects/libpng/files/libpng16/1.6.35/
+md5		678b7e696a62a193ed3503b04bf449d6			libpng-1.6.35.tar.xz
+sha1	0df1561aa1da610e892239348970d574b14deed0	libpng-1.6.35.tar.xz
 
 # Locally computed:
-sha256	2f1e960d92ce3b3abd03d06dfec9637dfbd22febf107a536b44f7a47c60659f6	libpng-1.6.34.tar.xz
-sha256	a247c24f82bacf0403fe2f3d5550493a91cdb575fe7036b764bda8cacf3efd9c	LICENSE
+sha256	23912ec8c9584917ed9b09c5023465d71709dce089be503c7867fec68a93bcd7	libpng-1.6.35.tar.xz
+sha256	f9850940c6606003eea9c8864b2a3f177eb5c963614aba5a3c5a24c47dd043ab	LICENSE

package/libpng/libpng.mk

@@ -4,7 +4,7 @@
 #
 ################################################################################
 
-LIBPNG_VERSION = 1.6.34
+LIBPNG_VERSION = 1.6.35
 LIBPNG_SERIES = 16
 LIBPNG_SOURCE = libpng-$(LIBPNG_VERSION).tar.xz
 LIBPNG_SITE = http://downloads.sourceforge.net/project/libpng/libpng$(LIBPNG_SERIES)/$(LIBPNG_VERSION)