brcmfmac: Fix memory leak in brcmf_usbdev_qinit

brcmfmac: Fix memory leak in brcmf_usbdev_qinit

commit 4282dc057d750c6a7dd92953564b15c26b54c22c upstream.

In the implementation of brcmf_usbdev_qinit() the allocated memory for
reqs is leaking if usb_alloc_urb() fails. Release reqs in the error
handling path.

Fixes: 71bb244ba2fd ("brcm80211: fmac: add USB support for bcm43235/6/8 chipsets")
Signed-off-by: Navid Emamdoost <navid.emamdoost@gmail.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>