tests: virpcimock: remove unused variable 'devid'

virpcimock.c:685:26: error: unused variable 'devid' [-Werror,-Wunused-variable]
    VIR_AUTOFREE(char *) devid = NULL;
                         ^

Fixes: 76b42294Signed-off-by: NJán Tomko <jtomko@redhat.com>

tests/virpcimock.c

@@ -682,7 +682,6 @@ pci_driver_find_by_path(const char *path)
 static struct pciDriver *
 pci_driver_find_by_driver_override(struct pciDevice *dev)
 {
-    VIR_AUTOFREE(char *) devid = NULL;
     VIR_AUTOFREE(char *) path = NULL;
     char tmp[32];
     size_t i;