ath9k_htc: Fix probe failure if CONFIG_USB_DEBUG enabled

Since the endpoint descriptors (EP3 & EP4) were changed from Interrupt
to Bulk type by firmware, the urb submission done on Bulk pipes.
And the recent commit "check the endpoint type against the pipe type"
added aditional error checking against pipe types under CONFIG_USB_DEBUG.

So bmAttribute has to be updated for both EP3 & EP4 before submitting
urbs on that pipe. This patch resolves the following failure.

[ 2215.710936] usb 1-1: usb_probe_device
[ 2215.710945] usb 1-1: configuration #1 chosen from 1 choice
[ 2215.711152] usb 1-1: adding 1-1:1.0 (config #1, interface 0)
[ 2215.711252] ath9k_hif_usb 1-1:1.0: usb_probe_interface
[ 2215.711255] ath9k_hif_usb 1-1:1.0: usb_probe_interface - got id
[ 2215.712780] usb 1-1: BOGUS urb xfer, pipe 3 != type 1
[ 2215.713782] usb 1-1: ath9k_htc: Unable to allocate URBs
[ 2215.713801] ath9k_hif_usb: probe of 1-1:1.0 failed with error -22

Reported-by: Ming Lei <tom.leiming@gmail.com>
Signed-off-by: Rajkumar Manoharan <rmanoharan@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>