[PATCH] powerpc: Fix build failure when CONFIG_USB=y

We are enabling USB unconditionally which results in following build failure

drivers/built-in.o: In function `tb_drom_read':
(.text+0x1b62b70): undefined reference to `usb_speed_string'
make: *** [vmlinux] Error

Enable USB only if USB_SUPPORT is set to avoid such failures

Signed-off-by: Pranith Kumar <redacted>
---
 arch/powerpc/platforms/44x/Kconfig | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/powerpc/platforms/44x/Kconfig

b/arch/powerpc/platforms/44x/Kconfig index 3e7deb2..82f2da2 100644

--- a/arch/powerpc/platforms/44x/Kconfig
+++ b/arch/powerpc/platforms/44x/Kconfig

@@ -215,7 +215,7 @@ config AKEBONO
 	select NET_VENDOR_IBM
 	select IBM_EMAC_EMAC4
 	select IBM_EMAC_RGMII_WOL
-	select USB
+	select USB if USB_SUPPORT
 	select USB_OHCI_HCD_PLATFORM if USB_OHCI_HCD
 	select USB_EHCI_HCD_PLATFORM if USB_EHCI_HCD
 	select MMC_SDHCI