selftests: drv-net: rss_ctx: fix the queue count check

Commit 0d6ccfe6b319 ("selftests: drv-net: rss_ctx: check for all-zero keys") added a skip exception if NIC has fewer than 3 queues enabled, but it's just constructing the object, it's not actually rising this exception.

Before:

# Exception| net.lib.py.utils.CmdExitFailure: Command failed: ethtool -X enp1s0 equal 3 hkey d1:cc:77:47:9d:ea:15:f2:b9:6c:ef:68:62:c0:45:d5:b0:99:7d:cf:29:53:40:06:3d:8e:b9:bc:d4:70:89:b8:8d:59:04:ea:a9:c2:21:b3:55:b8:ab:6b:d9:48:b4:bd:4c:ff:a5:f0:a8:c2 not ok 1 rss_ctx.test_rss_key_indir

After:

ok 1 rss_ctx.test_rss_key_indir # SKIP Device has fewer than 3 queues (or doesn't support queue stats)

---
I spotted that NIPA instances with 4 CPUs are failing this test case. They have only 4/2=2 queues. I bumped their CPU count to 6, but test is clearly wrong.

---
 tools/testing/selftests/drivers/net/hw/rss_ctx.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

index 7bb552f8b182..9838b8457e5a 100755
@@ -118,7 +118,7 @@ from lib.py import ethtool, ip, defer, GenerateTraffic, CmdExitFailure
 
     qcnt = len(_get_rx_cnts(cfg))
     if qcnt < 3:
-        KsftSkipEx("Device has fewer than 3 queues (or doesn't support queue stats)")
+        raise KsftSkipEx("Device has fewer than 3 queues (or doesn't support queue stats)")
 
     data = get_rss(cfg)
     want_keys = ['rss-hash-key', 'rss-hash-function', 'rss-indirection-table']

2.51.0