openbmc-machines: Remove unncessary CONFIG_HWMON

CONFIG_HWMON is implied by the drivers that use it, so we do not need to
specify it in the defconfigs.

Change-Id: I1c6e8679412f80dc0db69ef0f72a9c73e8602fb9
Signed-off-by: Joel Stanley <joel@jms.id.au>
diff --git a/meta-neptune/recipes-kernel/linux/linux-obmc/neptune.cfg b/meta-neptune/recipes-kernel/linux/linux-obmc/neptune.cfg
index 8789a62..9fc33b3 100644
--- a/meta-neptune/recipes-kernel/linux/linux-obmc/neptune.cfg
+++ b/meta-neptune/recipes-kernel/linux/linux-obmc/neptune.cfg
@@ -1,4 +1,3 @@
-CONFIG_HWMON=y
 CONFIG_SENSORS_TMP421=y
 CONFIG_SENSORS_MAX31785=y
 CONFIG_RTC_DRV_RV8803=y