clk: mediatek: fix uninitialized fields issue in INFRA_MUX struct

This patch adds missing initialization of fields in INFRA_MUX struct
which caused uart broken after any other infra mux being enabled by
'clk_prepare_enable'

diff --git a/drivers/clk/mediatek/clk-mt7981.c b/drivers/clk/mediatek/clk-mt7981.c
index 9707391..6081465 100644
--- a/drivers/clk/mediatek/clk-mt7981.c
+++ b/drivers/clk/mediatek/clk-mt7981.c
@@ -359,6 +359,7 @@
 		.id = _id, .mux_reg = (_reg) + 0x8,                            \
 		.mux_set_reg = (_reg) + 0x0, .mux_clr_reg = (_reg) + 0x4,      \
 		.mux_shift = _shift, .mux_mask = BIT(_width) - 1,              \
+		.gate_shift = -1, .upd_shift = -1,			       \
 		.parent_flags = _parents, .num_parents = ARRAY_SIZE(_parents), \
 		.flags = CLK_MUX_SETCLR_UPD | CLK_PARENT_MIXED,                \
 	}
diff --git a/drivers/clk/mediatek/clk-mt7986.c b/drivers/clk/mediatek/clk-mt7986.c
index c5cc772..f9d6f9c 100644
--- a/drivers/clk/mediatek/clk-mt7986.c
+++ b/drivers/clk/mediatek/clk-mt7986.c
@@ -366,6 +366,7 @@
 		.id = _id, .mux_reg = (_reg) + 0x8,                            \
 		.mux_set_reg = (_reg) + 0x0, .mux_clr_reg = (_reg) + 0x4,      \
 		.mux_shift = _shift, .mux_mask = BIT(_width) - 1,              \
+		.gate_shift = -1, .upd_shift = -1,			       \
 		.parent_flags = _parents, .num_parents = ARRAY_SIZE(_parents), \
 		.flags = CLK_MUX_SETCLR_UPD | CLK_PARENT_MIXED,                \
 	}
diff --git a/drivers/clk/mediatek/clk-mt7988.c b/drivers/clk/mediatek/clk-mt7988.c
index 8f4e8f4..73fd9c6 100644
--- a/drivers/clk/mediatek/clk-mt7988.c
+++ b/drivers/clk/mediatek/clk-mt7988.c
@@ -485,6 +485,7 @@
 		.id = _id, .mux_reg = _reg + 0x8, .mux_set_reg = _reg + 0x0,   \
 		.mux_clr_reg = _reg + 0x4, .mux_shift = _shift,                \
 		.mux_mask = BIT(_width) - 1, .parent = _parents,               \
+		.gate_shift = -1, .upd_shift = -1,			       \
 		.num_parents = ARRAY_SIZE(_parents),                           \
 		.flags = CLK_MUX_SETCLR_UPD | CLK_PARENT_TOPCKGEN,             \
 	}