Invoke make with -j$(nproc) for better parallelism.

storage/innobase/compile-innodb

@@ -22,4 +22,4 @@ MYSQL_ROOT="$(dirname ${0})/../.."
 cd ${MYSQL_ROOT}
 
 cmake -DWITH_INNOBASE_STORAGE_ENGINE:BOOL=ON
-make -j4
+make -j$(nproc)