Pass function pointer through interface (x_ConfigReg, x_QueryReg, x_Reset etc)

[bitshiftnetau]

Now that we have removed some functions from the parent jump tables, we need a way to access them.

Currently in the x_Init and x_RegDump fns we are simply accessing the ones outside the tables explicitly, before looping through the jump table.

However, in x_ConfigReg we are simply passing in a member config_register from the host object. This member is just an index for the fn in the jump table. Instead of doing this, simply pass in a function pointer and save it locally to ensure reentrance is not an issue.

This way, we can access fns inside the parent jump table OR the outside the jump table.