Using $(PWD) breaks builds when make was invoked from outside
of the kernel tree.
Signed-off-by: Yegor Yefremov <yegorslists@googlemail.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>
 #
 subdir-ccflags-$(CONFIG_USB_GADGET_DEBUG)      := -DDEBUG
 subdir-ccflags-$(CONFIG_USB_GADGET_VERBOSE)    += -DVERBOSE_DEBUG
-ccflags-y                              += -I$(PWD)/drivers/usb/gadget/udc
+ccflags-y                              += -I$(srctree)/drivers/usb/gadget/udc
 
 obj-$(CONFIG_USB_LIBCOMPOSITE) += libcomposite.o
 libcomposite-y                 := usbstring.o config.o epautoconf.o
 
 # USB peripheral controller drivers
 #
 
-ccflags-y                      := -I$(PWD)/drivers/usb/gadget/
-ccflags-y                      += -I$(PWD)/drivers/usb/gadget/udc/
+ccflags-y                      := -I$(srctree)/drivers/usb/gadget/
+ccflags-y                      += -I$(srctree)/drivers/usb/gadget/udc/
 
 # USB Functions
 usb_f_acm-y                    := f_acm.o
 
 # USB gadget drivers
 #
 
-ccflags-y                      := -I$(PWD)/drivers/usb/gadget/
-ccflags-y                      += -I$(PWD)/drivers/usb/gadget/udc/
-ccflags-y                      += -I$(PWD)/drivers/usb/gadget/function/
+ccflags-y                      := -I$(srctree)/drivers/usb/gadget/
+ccflags-y                      += -I$(srctree)/drivers/usb/gadget/udc/
+ccflags-y                      += -I$(srctree)/drivers/usb/gadget/function/
 
 g_zero-y                       := zero.o
 g_audio-y                      := audio.o