Reed-Solomon (zfec): fixed fec_new fail

With current zfec code, fec_init() needs to be called prior to fec_new(),
otherwise the later one returns NULL.

\+ updated submodule to the current zfec version (requiring fec_init();
but UG will compile with the older zfec version as well)

src/host.cpp

@@ -99,6 +99,13 @@
 #define X11_LIB_NAME "libX11.so.6"
 #endif
 
+#ifdef HAVE_FEC_INIT
+#define restrict __restrict // not a C++ keyword
+extern "C" {
+#include <fec.h>
+}
+#endif
+
 #ifdef __linux__
 #include <mcheck.h>
 #endif
@@ -431,6 +438,10 @@ struct init_data *common_preinit(int argc, char *argv[])
                 incompatible_features = true;
         }
 
+#ifdef HAVE_FEC_INIT
+        fec_init();
+#endif
+
         return new init_data{init};
 }