i2c: piix4: Standardize log messages

Use exactly the same log messages in the legacy setup function and the
SB800+ setup function. This way strings can be reused, which saves
some bytes in the generated binary.

Signed-off-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>