RDMA/irdma: Fix vf_id size to u16 to avoid overflow

Correctly size the vf_id to u16 to avoid overflow.

Signed-off-by: Jay Bhat <jay.bhat@intel.com>
Signed-off-by: Tatyana Nikolova <tatyana.e.nikolova@intel.com>
Link: https://patch.msgid.link/20251031021726.1003-6-tatyana.e.nikolova@intel.com
Signed-off-by: Leon Romanovsky <leon@kernel.org>