[PATCH] zd1211rw: removed noisy debug messages

While developing the driver we added a lot of debug messages for
setting hardware registers. These messages make the reading of the
log files difficult and are of no use anymore. This patch removes
those messages in zd_chip.c.

Signed-off-by: Ulrich Kunitz <kune@deine-taler.de>
Signed-off-by: Daniel Drake <dsd@gentoo.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>