module: Move all into module/

No functional changes.

This patch moves all module related code into a separate directory,
modifies each file name and creates a new Makefile. Note: this effort
is in preparation to refactor core module code.

Reviewed-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Aaron Tomlin <atomlin@redhat.com>
Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>