clk: renesas: r8a77990: Add Z2 clock

Adds support for R-Car E3 (r8a77990) Z2 clock.

Signed-off-by: Takeshi Kihara <takeshi.kihara.df@renesas.com>
[simon: reworked changelog; rebased]
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>

drivers/clk/renesas/r8a77990-cpg-mssr.c

@@ -81,6 +81,7 @@ static const struct cpg_core_clk r8a77990_core_clks[] __initconst = {
 	/* Core Clock Outputs */
 	DEF_FIXED("za2",       R8A77990_CLK_ZA2,   CLK_PLL0D24,    1, 1),
 	DEF_FIXED("za8",       R8A77990_CLK_ZA8,   CLK_PLL0D8,     1, 1),
+	DEF_GEN3_Z("z2",       R8A77990_CLK_Z2,    CLK_TYPE_GEN3_Z, CLK_PLL0, 4, 8),
 	DEF_FIXED("ztr",       R8A77990_CLK_ZTR,   CLK_PLL1,       6, 1),
 	DEF_FIXED("zt",        R8A77990_CLK_ZT,    CLK_PLL1,       4, 1),
 	DEF_FIXED("zx",        R8A77990_CLK_ZX,    CLK_PLL1,       3, 1),