ehci_alloc_itd_chain() tweak

[Michael W. Bombardieri]

Hello,

In ehci_alloc_itd_chain(), no need to compute uframes if nframes
is zero and function would return early.

- Michael


Index: src/sys/dev/usb/ehci.c
===================================================================
RCS file: /cvs/src/sys/dev/usb/ehci.c,v
retrieving revision 1.200
diff -u -p -u -r1.200 ehci.c
--- src/sys/dev/usb/ehci.c      15 May 2017 10:52:08 -0000      1.200
+++ src/sys/dev/usb/ehci.c      22 Nov 2017 07:08:43 -0000
@@ -3385,9 +3385,9 @@ ehci_alloc_itd_chain(struct ehci_softc *
                break;
        }
        nframes = (xfer->nframes + (ufrperframe - 1)) / ufrperframe;
-       uframes = 8 / ufrperframe;
        if (nframes == 0)
                return (1);
+       uframes = 8 / ufrperframe;
 
        for (i = 0; i < nframes; i++) {
                uint32_t froffs = offs;