bnxt_en: Linearize TX SKB if the fragments exceed the max

If skb_shinfo(skb)->nr_frags excceds what the chip can support,
linearize the SKB and warn once to let the user know.
net.core.max_skb_frags can be lowered, for example, to avoid the
issue.

Fixes: 3948b059 ("net: introduce a config option to tweak MAX_SKB_FRAGS")
Reviewed-by: Somnath Kotur <somnath.kotur@broadcom.com>
Reviewed-by: Kalesh AP <kalesh-anakkur.purayil@broadcom.com>
Reviewed-by: Andy Gospodarek <andrew.gospodarek@broadcom.com>
Signed-off-by: Michael Chan <michael.chan@broadcom.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://patch.msgid.link/20250321211639.3812992-3-michael.chan@broadcom.com


Signed-off-by: Jakub Kicinski <kuba@kernel.org>