This updates flac to the new upstream release v1.3.1 to fix two known CVEs.
Additionally the commit changes the following:
* Drop custom Build/Configure recipe in favor to CONFIGURE_ARGS
* Refreshes patches and removes changes to *.in files since they're
regenerated by autoreconf anyway
* Remove now obsolete 020-libFLAC-remove-altivec-options.patch
* Add an md5sum for the source archive
* Passes --enable-static to configure to force producing a libflac.a
Signed-off-by: Jo-Philipp Wich <jow@openwrt.org>
Ted Hess