clk: renesas: r8a77995: Add ZA2 clock

R-Car D3 ZA2 clock is from PLL0D3 or S0,
and it can be controlled by ZA2CKCR.
It is needed for R-Car Sound, but is not used so far.
Using default settings is very enough at this point.
This patch adds it by DEF_FIXED().
Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Link: https://lore.kernel.org/r/87pmxclrmy.wl-kuninori.morimoto.gx@renesas.comSigned-off-by: Geert Uytterhoeven <geert+renesas@glider.be>

drivers/clk/renesas/r8a77995-cpg-mssr.c

@@ -75,6 +75,7 @@ static const struct cpg_core_clk r8a77995_core_clks[] __initconst = {
 	DEF_RATE(".oco",       CLK_OCO,            8 * 1000 * 1000),
 
 	/* Core Clock Outputs */
+	DEF_FIXED("za2",       R8A77995_CLK_ZA2,   CLK_PLL0D3,     2, 1),
 	DEF_FIXED("z2",        R8A77995_CLK_Z2,    CLK_PLL0D3,     1, 1),
 	DEF_FIXED("ztr",       R8A77995_CLK_ZTR,   CLK_PLL1,       6, 1),
 	DEF_FIXED("zt",        R8A77995_CLK_ZT,    CLK_PLL1,       4, 1),