flac/foreign_metadata: Fix for odd RIFF chunk size

Accept odd values to ckSize of RIFF chunk. FLAC should read these
but should avoid creating them.

Patch-from: lvqcl <lvqcl.mail@gmail.com>
Closes: https://sourceforge.net/p/flac/support-requests/152/
Closes: https://sourceforge.net/p/flac/bugs/419/
1 file changed