fib_nexthop_nongw.sh from ubuntu_kernel_selftests failed on F-kvm (config not enabled)

This bug was filed because we used to hint this failure with bug 1990800, which has been closed. Thus we need a new report to keep track of.

This test would require the CONFIG_DUMMY config to be enabled. But we don't have it enabled on F-kvm kernel. Thus it's failing:

 make: Entering directory '/home/ubuntu/autotest/client/tmp/ubuntu_kernel_selftests/src/linux/tools/testing/selftests/net'
 make --no-builtin-rules ARCH=x86 -C ../../../.. headers_install
 make[1]: Entering directory '/home/ubuntu/autotest/client/tmp/ubuntu_kernel_selftests/src/linux'
   INSTALL ./usr/include
 make[1]: Leaving directory '/home/ubuntu/autotest/client/tmp/ubuntu_kernel_selftests/src/linux'
 TAP version 13
 1..1
 # selftests: net: fib_nexthop_nongw.sh
 # Error: Unknown device type.
 # Cannot find device "eth0"
 # Cannot find device "eth0"
 # TEST: nexthop: get route with nexthop without gw [ OK ]
 # TEST: nexthop: ping through nexthop without gw [FAIL]
 not ok 1 selftests: net: fib_nexthop_nongw.sh # exit=1

For this lack of config failure in J/K, it will be fixed in bug 1998244