spi_nxp_lpspi: Remove call to MasterInit

For optimization purpose, remove calls to SDK. Since we know exactly
what we want, this results in smaller code size.

Also, this code calculates the SCK parameters more efficiently than the
SDK driver did it by using a binary (instead of linear) search.

Lastly, remove call to LPSPI_Reset in the init call and replace with
native driver code, and remove inclusion of SDK header.

Signed-off-by: Declan Snyder <declan.snyder@nxp.com>