wic: renamd direct_plugin.py -> direct.py

As this files is located in plugins/imager subdirectory it's
obvious that it's an imager plugin. Renamed to direct.py to
be consistent with plugin naming scheme.

[YOCTO #10619]

(From OE-Core rev: d5db8c2ee91bdd51bfbb2ebf61aea8ff0378d512)

Signed-off-by: Ed Bartosh <ed.bartosh@linux.intel.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

diff --git a/scripts/lib/wic/plugins/imager/direct_plugin.py b/scripts/lib/wic/plugins/imager/direct.py
similarity index 100%
rename from scripts/lib/wic/plugins/imager/direct_plugin.py
rename to scripts/lib/wic/plugins/imager/direct.py