clk: meson: gxbb: add the fractional part of the fixed_pll

The fixed_pll of gxbb and gxl also has a fractional parameter. This has
not been a problem so far because the fractional part is actually set
to 0 on these platforms, so the rate remains correct when it is ignored.
Still, it is better represent the pll the way it is, so add the frac
parameter now

Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>

drivers/clk/meson/gxbb.c

@@ -202,6 +202,11 @@ static struct meson_clk_pll gxbb_fixed_pll = {
 		.shift   = 16,
 		.width   = 2,
 	},
+	.frac = {
+		.reg_off = HHI_MPLL_CNTL2,
+		.shift   = 0,
+		.width   = 12,
+	},
 	.lock = &meson_clk_lock,
 	.hw.init = &(struct clk_init_data){
 		.name = "fixed_pll",