bnxt_en: Move RSS table fill outside __bnxt_hwrm_vnic_set_rss()

bnxt_en: Move RSS table fill outside __bnxt_hwrm_vnic_set_rss()

This is a refactor patch with no change in behavior.  The caller
will now fill the RSS table before calling __bnxt_hwrm_vnic_set_rss().
In the next patch, we'll add code to determine the default ring for
the VNIC when we fill the RSS table.

Reviewed-by: Kalesh AP <kalesh-anakkur.purayil@broadcom.com>
Reviewed-by: Pavan Chebbi <pavan.chebbi@broadcom.com>
Signed-off-by: Shravya KN <shravya.k-n@broadcom.com>
Signed-off-by: Michael Chan <michael.chan@broadcom.com>
Link: https://patch.msgid.link/20260731190937.807270-2-michael.chan@broadcom.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>