WL#9816: Do not build/package/test embedded server

This is part of overall work to remove the libmysqld embedded server

This worklog will
- Remove/Cleanup all cmake related code pertaining to embedded server
- Remove/Cleanup embedded server from RMP and Debian packages
- Remove embedded tests from our mtr test collections
- Remove all source code in the libmysqld directory

This worklog will *not*
- Clean up the mtr test suite
- Clean up any C/C++ source code

User Documentation
==================

http://dev.mysql.com/doc/relnotes/mysql/8.0/en/news-8-0-1.html

Remaining part of documentation task is to remove all mention of libmysqld from
refman-8.0.

cmake things to remove: any name with EMBEDDED in it

WITH_EMBEDDED_SERVER

MYSQLD_STATIC_EMBEDDED_PLUGIN_LIBS
MYSQLD_STATIC_EMBEDDED_COMPONENT_LIBS

DEFAULT_SECURE_FILE_PRIV_EMBEDDED_DIR
INSTALL_SECURE_FILE_PRIV_EMBEDDEDDIR_DEB
INSTALL_SECURE_FILE_PRIV_EMBEDDEDDIR_FREEBSD
INSTALL_SECURE_FILE_PRIV_EMBEDDEDDIR_GLIBC
INSTALL_SECURE_FILE_PRIV_EMBEDDEDDIR_OSX
INSTALL_SECURE_FILE_PRIV_EMBEDDEDDIR_RPM
INSTALL_SECURE_FILE_PRIV_EMBEDDEDDIR_SLES
INSTALL_SECURE_FILE_PRIV_EMBEDDEDDIR_STANDALONE
INSTALL_SECURE_FILE_PRIV_EMBEDDEDDIR_SVR4
INSTALL_SECURE_FILE_PRIV_EMBEDDEDDIR_TARGZ
INSTALL_SECURE_FILE_PRIV_EMBEDDEDDIR_WIN

FOR MYSQL_ADD_PLUGIN, remove arguments NOT_FOR_EMBEDDED RECOMPILE_FOR_EMBEDDED

Remove entirely: libmysqld/ including libmysqld/CMakeLists.txt

===========
Remove embedded server from all packages:
WiX, debian, docker, fedora, oel, sles

===========
No tests are removed in this worklog.

Change test collections to not run any embedded tests
collections/default.daily
collections/default.push
collections/default.release
collections/default.weekly
collections/default.weekly
collections/default.weekly.basic
collections/mysql-trunk-stage.push

============
Remove entirely: directory libmysqld/
This removes executables 
mysql_embedded
mysqltest_embedded
mysql_client_test_embedded

This removes libraries
mysqlserver.lib on windows
libmysqld.a on unix
libmysqld.so (optional on unix)


Remove --libmysqld-libs from the script 'mysql_config'