witherspoon: Remove machine specific host UART over VGA packages

These packages are now part of meta-phosphor, so they can be removed
from the meta-witherspoon directory.

The feature is still enabled by their inclusion in
meta-witherspoon/recipes-phosphor/images/obmc-phosphor-image.bbappend.

Change-Id: I653e2b3c96bf9e9ab4d607f60355ff68432e855a
Signed-off-by: Joel Stanley <joel@jms.id.au>
7 files changed