The disable function can be the same as for MG phy since the same
registers are used. The others are different as registers changed,
also adding a empty dkl_pll_write() to be implemented later.

v2:
Setting the right HIP_INDEX_REG bits (José)

v3:
Masking non-computed registers of mg_pll_tdc_coldst_bias
when getting hardware state
Sharing mg_pll_enable() with TGL
Reviewed-by: Imre Deak <imre.deak@intel.com>
Acked-by: Lucas De Marchi <lucas.demarchi@intel.com>
Signed-off-by: José Roberto de Souza <jose.souza@intel.com>
Signed-off-by: Lucas De Marchi <lucas.demarchi@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190924210040.142075-1-jose.souza@intel.com