net/bnxt: fix firmware version query

net/bnxt: fix firmware version query

UBSan testing revealed undefined shift here.

The firmware returns the version in bytes; and shifting a 8 bit
quantity here can lead to undefined behaviour or truncation.
The fix is to promote the bytes to 32 bit before shifting.

Bugzilla ID: 838
Fixes: 9a891c1764ea ("net/bnxt: update HWRM to version 1.9.2")
Cc: stable@dpdk.org
Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
Acked-by: Somnath Kotur <somnath.kotur@broadcom.com>
Acked-by: Ajit Khaparde <ajit.khaparde@broadcom.com>