ionic: extend the QSFP module sprom for more pages

ionic: extend the QSFP module sprom for more pages

Some QSFP modules have more eeprom to be read by ethtool than
the initial high and low page 0 that is currently available
in the DSC's ionic sprom[] buffer.  Since the current sprom[]
is baked into the middle of an existing API struct, to make
the high end of page 1 and page 2 available a block is carved
from a reserved space of the existing port_info struct and the
ionic_get_module_eeprom() service is taught how to get there.

Newer firmware writes the additional QSFP page info here,
yet this remains backward compatible because older firmware
sets this space to all 0 and older ionic drivers do not use
the reserved space.

Reviewed-by: Brett Creeley <brett.creeley@amd.com>
Signed-off-by: Shannon Nelson <shannon.nelson@amd.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://patch.msgid.link/20250415231317.40616-2-shannon.nelson@amd.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>