ipq806x: enable usb support

This change doesn't make USB functional but it does make it selectable
from a configuration perspective.

Signed-off-by: Mathieu Olivari <mathieu@codeaurora.org>

git-svn-id: svn://svn.openwrt.org/openwrt/trunk@45259 3c298f89-4303-0410-b956-a3cf2f4a3e73

target/linux/ipq806x/config-3.18

@@ -352,6 +352,7 @@ CONFIG_UEVENT_HELPER_PATH=""
 CONFIG_UID16=y
 CONFIG_UNCOMPRESS_INCLUDE="debug/uncompress.h"
 CONFIG_UNINLINE_SPIN_UNLOCK=y
+CONFIG_USB_SUPPORT=y
 CONFIG_USE_OF=y
 CONFIG_VECTORS_BASE=0xffff0000
 # CONFIG_VFIO is not set

target/linux/ipq806x/config-4.0

@@ -365,6 +365,7 @@ CONFIG_UEVENT_HELPER_PATH=""
 CONFIG_UID16=y
 CONFIG_UNCOMPRESS_INCLUDE="debug/uncompress.h"
 CONFIG_UNINLINE_SPIN_UNLOCK=y
+CONFIG_USB_SUPPORT=y
 CONFIG_USE_OF=y
 CONFIG_VECTORS_BASE=0xffff0000
 CONFIG_VFP=y