WL#1151: make build process cross-compile friendly

Previously the High-Level Description for this task
mentioned certain things that could be done with autotools.
That's removed, since autotools won't be supported
starting with MySQL 5.5. See November 16 email
"Cancel seven autotools worklog tasks"
[ mysql intranet archive ] /mail.php?folder=4&mail=37663
See progress field for 2010-11-17.
See also BUG#2706 mysql not ready for cross-compilation.