ecdsa-s2c: block in module

Co-authored-by: Marko Bencun <mbencun+pgp@gmail.com>
Co-authored-by: Jonas Nick <jonasd.nick@gmail.com>

contrib/travis.sh

@@ -17,6 +17,7 @@ fi
     --with-test-override-wide-multiply="$WIDEMUL" --with-bignum="$BIGNUM" --with-asm="$ASM" \
     --enable-ecmult-static-precomputation="$STATICPRECOMPUTATION" --with-ecmult-gen-precision="$ECMULTGENPRECISION" \
     --enable-module-ecdh="$ECDH" --enable-module-recovery="$RECOVERY" \
+    --enable-module-ecdsa-s2c="$ECDSA_S2C" \
     --enable-module-rangeproof="$RANGEPROOF" --enable-module-whitelist="$WHITELIST" --enable-module-generator="$GENERATOR" \
     --enable-module-schnorrsig="$SCHNORRSIG"  --enable-module-musig="$MUSIG"\
     --with-valgrind="$WITH_VALGRIND" \