Disable ethernet over usb on SMARC-sAMX6i

Otherwise the device isn't auto detected by adb on windows.

Task-number: QTBUG-51877
Change-Id: Ia52d4dd8e6cc10aec82b0ea6d50f3b00f412d7d5
Reviewed-by: David Schulz <david.schulz@theqtcompany.com>

meta-smx6-extras/recipes/linux/linux-smx6_3.14.28.bbappend

@@ -20,6 +20,10 @@
 ##############################################################################
 
 do_configure_prepend() {
+    sed -e '/CONFIG_USB_FUNCTIONFS_ETH=/d' \
+        -e '/CONFIG_USB_FUNCTIONFS_RNDIS=/d' \
+        -i ${WORKDIR}/defconfig
+
     echo "CONFIG_NAMESPACES=y"              >> ${WORKDIR}/defconfig
     echo "CONFIG_FHANDLE=y"                 >> ${WORKDIR}/defconfig
     echo "CONFIG_CGROUPS=y"                 >> ${WORKDIR}/defconfig