meta-zaius: Add kernel defconfig appends

Add Zaius specific driver configs for RTC, 1-wire thermal sensor, and
I2C mux.

Signed-off-by: Xo Wang <xow@google.com>
Change-Id: If265035e7a2f03e1a890c512f86cce27d091391c
diff --git a/meta-zaius/recipes-kernel/linux/linux-obmc_%.bbappend b/meta-zaius/recipes-kernel/linux/linux-obmc_%.bbappend
new file mode 100644
index 0000000..543bfe0
--- /dev/null
+++ b/meta-zaius/recipes-kernel/linux/linux-obmc_%.bbappend
@@ -0,0 +1,2 @@
+FILESEXTRAPATHS_prepend := "${THISDIR}/linux-obmc:"
+SRC_URI += "file://zaius.cfg"