Added more help text in case mysql_install_db fails.

scripts/mysql_install_db.sh

@@ -211,6 +211,11 @@ cannot_find_file()
   echo "If you compiled from source, you need to run 'make install' to"
   echo "copy the software into the correct location ready for operation."
   echo
+  echo "If you compiled from source, you need to either run 'make install' to"
+  echo "copy the software into the correct location ready for operation."
+  echo "If you don't want to do a full install, you can use the --srcdir"
+  echo "option to only install the mysql database and privilege tables"
+  echo
   echo "If you are using a binary release, you must either be at the top"
   echo "level of the extracted archive, or pass the --basedir option"
   echo "pointing to that location."