clk: renesas: rzv2h-cpg: Extract PLL calculation helpers into shared library

Move the RZ/V2H PLL and divider parameter calculation helpers from
rzv2h-cpg.c into a new reusable library.

Introduce the CLK_RZV2H_CPG_LIB Kconfig symbol and add
rzv2h-cpg-lib.c to host the PLL parameter search algorithms currently
implemented by rzv2h_get_pll_pars() and rzv2h_get_pll_divs_pars().
Export the helpers as rzv2h_cpg_get_pll_pars() and
rzv2h_cpg_get_pll_divs_pars() for use by other drivers.

Update the public clock header to expose the new interfaces and provide
compatibility aliases for the existing helper names, avoiding build
breakage for current users while allowing future conversions to the new
API.

This prepares for reuse of the PLL and divider calculation logic by
other Renesas clock drivers, including upcoming RZ/T2H and RZ/N2H CPG
support, without duplicating the implementation.

Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://patch.msgid.link/20260618181949.3036280-5-prabhakar.mahadev-lad.rj@bp.renesas.com
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>

0 files changed, 0 insertions, 0 deletions