clk: meson: meson8b: mark clk81 as critical

Disabling clk81 results in an immediate freeze of the whole system. This
can happen "accidentally" when the last child-clock of clk81 is disabled
(in this case the common clock framework also disables clk81, even if it
was only enabled indirectly before).
Signed-off-by: NMartin Blumenstingl <martin.blumenstingl@googlemail.com>
Signed-off-by: NJerome Brunet <jbrunet@baylibre.com>
Acked-by: NNeil Armstrong <narmstrong@baylibre.com>
Signed-off-by: NNeil Armstrong <narmstrong@baylibre.com>

drivers/clk/meson/meson8b.c

@@ -399,7 +399,7 @@ struct clk_gate meson8b_clk81 = {
 		.ops = &clk_gate_ops,
 		.parent_names = (const char *[]){ "mpeg_clk_div" },
 		.num_parents = 1,
-		.flags = (CLK_SET_RATE_PARENT | CLK_IGNORE_UNUSED),
+		.flags = (CLK_SET_RATE_PARENT | CLK_IS_CRITICAL),
 	},
 };