usb: dwc3: ep0: fix for dead code
usb: dwc3: ep0: fix for dead code

commit 6856d30 (usb: dwc3: ep0: return early
on NULL requests) tried to fix a minor corner
case where we could dereference a NULL pointer
but it also ended up introducing some dead code.

Unfortunately, that dead code, if reached, could
end up starving the endpoint request list because
a request would never be given back when it should.

Fix this by moving the check for empty request list
before its first use.

Reported-by: Dave Jones <d5ec0d24602845f6f4b6a35ef729998d1fba5507@redhat.com>
Signed-off-by: Felipe Balbi <94dddeeef08b001e003cce128ddc162a4e2c6cd2@ti.com>

KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs