ARM: uniphier: drop DCC micro support card support

Historically (for compatibility with very old platforms), two
different types of micro support cards have been used with the
UniPhier SoC development boards.  It has been painful to maintain
both.  Having one of them is enough.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Simon Glass <sjg@chromium.org>