hwmon: (lm90) Do not report 'busy' status bit as alarm

commit cdc5287a upstream.

Bit 7 of the status register indicates that the chip is busy
doing a conversion. It does not indicate an alarm status.
Stop reporting it as alarm status bit.

Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>