usb: msm8974: Select USB_ARCH_HAS_XHCI by default

msm8974 supports super-speed usb3.0 xHCI interface.

Change-Id: I17de8c9caa16cd0b73782f41ccf69f26133a4f40
Signed-off-by: Ido Shayevitz <idos@codeaurora.org>
diff --git a/drivers/usb/Kconfig b/drivers/usb/Kconfig
index ceefb23..3e15ea7 100644
--- a/drivers/usb/Kconfig
+++ b/drivers/usb/Kconfig
@@ -53,6 +53,7 @@
 # some non-PCI HCDs implement xHCI
 config USB_ARCH_HAS_XHCI
 	boolean
+	default y if ARCH_MSM8974
 	default PCI
 
 menuconfig USB_SUPPORT