Older Thor2 firmware serves key context allocation requests very
slowly, about a second each. The driver allocates key contexts in
batches of 128, so setting up 500k sessions takes roughly 3900
requests and driver load appears to hang.
Enable hardware kTLS only when the firmware's HWRM interface version
is 1.10.3.99 or newer. Keep the full four-part version in
hwrm_spec_code_ext for the comparison.
Also add a disable_hw_ktls loader tunable that turns hardware kTLS off
for a device without unloading kTLS support, which helps isolate kTLS
problems in the field.