phy: lynx-28g: move data structures to core

phy: lynx-28g: move data structures to core

The goal is to avoid duplicating the core data structures when
introducing the new lynx-10g driver.

We move the following to phy-fsl-lynx-core:
- struct lynx_28g_pll -> struct lynx_pll. This has some
  hardware-specific register fields which need to become hardware
  agnostic (the PLL register layout is different for Lynx 10G), So:
  - PLLnRSTCTL_DIS(pll->rstctl) becomes !pll->enabled
  - PLLnRSTCTL_LOCK(pll->rstctl) becomes pll->locked
  - FIELD_GET(PLLnCR1_FRATE_SEL, pll->cr1) becomes pll->frate_sel
  - FIELD_GET(PLLnCR0_REFCLK_SEL, pll->cr0) becomes pll->refclk_sel
- struct lynx_28g_lane -> struct lynx_lane
- struct lynx_28g_priv -> struct lynx_priv
  - field lane[LYNX_28G_NUM_LANE] has to be dynamically allocated. Not
    all Lynx 10G SerDes blocks have 8 lanes.
- LYNX_28G_NUM_PLL -> LYNX_NUM_PLL. This is an architectural constant
  which is the same for Lynx 10G as well.

To avoid major noise in the lynx-28g driver, we keep compatibility shims
(for now) where the old lynx_28g names are preserved, but translate to
the common data structures.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Link: https://patch.msgid.link/20260610151952.2141019-5-vladimir.oltean@nxp.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>