ice: prevent tstamp ring allocation for non-PF VSI types

Summary

In the Linux kernel, the following vulnerability has been resolved: ice: prevent tstamp ring allocation for non-PF VSI types The pf->txtime_txqs bitmap tracks which Tx queues have ETF (Earliest TxTime First) offload enabled. This bitmap is indexed by queue number and is set by ice_offload_txtime(), which only operates on PF VSI queues. However, ice_is_txtime_ena() does not check the VSI type before consulting the bitmap. When ETF offload is enabled on PF Tx queue 0, bit 0 is set in pf->txtime_txqs. During a subsequent PCI reset rebuild, the CTRL VSI's Tx queue 0 is reconfigured and ice_is_txtime_ena() is called for that ring. Since it only checks pf->txtime_txqs by queue index without distinguishing VSI type, it finds bit 0 set and returns true, matching the PF VSI's ETF queue, not the CTRL VSI's. This causes ice_vsi_cfg_txq() to spuriously allocate a tstamp_ring for the CTRL VSI ring. Since CTRL VSI rings have no associated netdev, ice_clean_tx_ring() takes an early return at the !netdev check before reaching ice_free_tx_tstamp_ring(), leaking the allocation. Each PCI reset leaks one 64-byte tstamp_ring. Fix this by restricting ice_is_txtime_ena() to return true only for PF VSI rings, since txtime_txqs is only meaningful for PF VSI queues.