[otbn] add domain parameters for P-256 to lib
[otbn] add domain parameters for P-256 to lib

Adds the P-256 domain parameters to the data section
in the lib's assembly file and removes them from
the instruction stream.

Signed-off-by: Felix Miller <43d2a12732a784b305469416c0ba5ce1795e752a@gi-de.com>

lowRISC/opentitan,lowRISC/opentitan,lowRISC/opentitan,lowRISC/opentitan,lowRISC/opentitan,lowRISC/opentitan