common/console.c: Drop sandbox special-case console code

As done in commit da229e4e [sandbox: Drop special-case sandbox console code],
this patch drops the sandbox special-case code in vprintf() that was
missed by Simon at that time.

Signed-off-by: Stefan Roese <sr@denx.de>
Cc: Simon Glass <sjg@chromium.org>
Acked-by: Simon Glass <sjg@chromium.org>