runtime/katautils: PFlash should be initialized

newQemuHypervisorConfig() sets it to an empty slice. We have to set the
same in the test config otherwise it is nil and reflect DeepEqual would
fail.

Signed-off-by: Peng Tao <bergwolf@hyper.sh>

src/runtime/pkg/katautils/config_test.go

@@ -172,6 +172,7 @@ func createAllRuntimeConfigFiles(dir, hypervisor string) (config testRuntimeConf
 		SharedFS:              sharedFS,
 		VirtioFSDaemon:        virtioFSdaemon,
 		VirtioFSCache:         defaultVirtioFSCacheMode,
+		PFlash:                []string{},
 		SGXEPCSize:            epcSize,
 	}