configure: add avx2 enabled log

Signed-off-by: James Almer <jamrial@gmail.com>

configure

@@ -6649,6 +6649,7 @@ if enabled x86; then
     echo "SSSE3 enabled             ${ssse3-no}"
     echo "AESNI enabled             ${aesni-no}"
     echo "AVX enabled               ${avx-no}"
+    echo "AVX2 enabled              ${avx2-no}"
     echo "XOP enabled               ${xop-no}"
     echo "FMA3 enabled              ${fma3-no}"
     echo "FMA4 enabled              ${fma4-no}"