* my_aes.h doesn't compile without my_global.h
* typo in a comment
* redundant condition
* if encryption plugin fails, there's no encryption_key_manager
at plugin deinit time
* encryption plugin tests must run when plugin.so is present,
not when a plugin is active (otherwise the test will be skipped
when plugin fails to initialize).
file_key_management_plugin is used
Fixed error handling and added disabling InnoDB redo log encryption
if encryption key management plugin is not there.
