tests: skip raid testing on 4.[1,2] fc24 kernels

Hopefull 4.3 will be fixed and test will be updated to let
raid test running again.

Meanwhile using md-raid may effectively kill kernel,
so leave at least other tests running.

test/lib/aux.sh

@@ -1108,6 +1108,14 @@ have_raid() {
 		return 1;
 	}
 	target_at_least dm-raid "$@"
+
+	# some kernels have broken mdraid bitmaps, don't use them!
+	# may oops kernel, we know for sure all FC24 are currently broken
+	# in general any 4.1, 4.2 is likely useless unless patched
+	# hopefully 4.3 will be patched
+	case "$(uname -r)" in
+	  4.[123].*fc24*) return 1 ;;
+	esac
 }
 
 have_cache() {