dma_pool_alloc() require sleeping context when called with GFP_KERNEL
argument.  Hence release the spin lock before calling dma_pool_alloc().

usb_ep_alloc_request can also be called with non-atomic GFP flags.  Hence
get rid off spin lock while allocation request memory.

Use GFP_ATOMIC flag for allocating request for ep0 in interrupt handler.
Signed-off-by: Pavankumar Kondeti <pkondeti@codeaurora.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>