package/vdr: bump to version 2.4.6

package/vdr: bump to version 2.4.6

- Drop patches (already in version)
- pkg-config can be used to retrieve dependencies since
  https://projects.vdr-developer.org/git/vdr.git/commit?id=f5dba03447fa73da6e181ead7fb98c2b0a2fed41
  so use it and drop unneeded workarounds such as VDR_INCLUDE_DIRS
- Update indentation in hash file (two spaces)

https://projects.vdr-developer.org/git/vdr.git/tree/HISTORY?id=V20406

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