package/vdr: bump to version 2.5.6

- Use github mirror to get latest release
- This bump will fix a build failure with gcc 11 thanks to
  http://autobuild.buildroot.org/results/3dda387a765f7980c0bb567aeb0f0d86328ae876

https://github.com/vdr-projects/vdr/blob/2.5.6/HISTORY

Fixes:
 - http://autobuild.buildroot.org/results/3dda387a765f7980c0bb567aeb0f0d86328ae876

Signed-off-by: Fabrice Fontaine <fontaine.fabrice@gmail.com>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>

package/vdr/vdr.hash

@@ -1,5 +1,3 @@
-# From https://www.linuxtv.org/pipermail/vdr/2020-December/029578.html
-md5  aa91614159ae2db45655d35918e2c24e  vdr-2.4.6.tar.bz2
 # Locally computed
-sha256  c8993babf2a878a0fba84558de1e35f042c3c66f7c1ec569eea00a3af1014e4b  vdr-2.4.6.tar.bz2
+sha256  27026b78a663758211d15c83a21555e28d91ab640c6d4f6cdd860f2abf1cae84  vdr-2.5.6.tar.gz
 sha256  ddb9db7630752f8fdc6898f7c99a99eaeeac5213627ecb093df9c82f56175dc7  COPYING

package/vdr/vdr.mk

@@ -4,9 +4,8 @@
 #
 ################################################################################
 
-VDR_VERSION = 2.4.6
-VDR_SOURCE = vdr-$(VDR_VERSION).tar.bz2
-VDR_SITE = ftp://ftp.tvdr.de/vdr
+VDR_VERSION = 2.5.6
+VDR_SITE = $(call github,vdr-projects,vdr,$(VDR_VERSION))
 VDR_LICENSE = GPL-2.0+
 VDR_LICENSE_FILES = COPYING
 VDR_CPE_ID_VENDOR = tvdr