nir: use {0} initializer instead of {} to fix MSVC build

Trivial change.

Fixes: c6ee46a75 ("nir: Add nir_alu_srcs_negative_equal")

src/compiler/nir/nir_instr_set.c

@@ -438,7 +438,7 @@ nir_alu_srcs_negative_equal(const nir_alu_instr *alu1,
                                             alu1->dest.dest.ssa.bit_size);
    }
 
-   uint8_t alu1_swizzle[4] = {};
+   uint8_t alu1_swizzle[4] = {0};
    nir_src alu1_actual_src;
    const struct nir_alu_instr *const neg1 = get_neg_instr(&alu1->src[src1].src);
 
@@ -455,7 +455,7 @@ nir_alu_srcs_negative_equal(const nir_alu_instr *alu1,
          alu1_swizzle[i] = i;
    }
 
-   uint8_t alu2_swizzle[4] = {};
+   uint8_t alu2_swizzle[4] = {0};
    nir_src alu2_actual_src;
    const struct nir_alu_instr *const neg2 = get_neg_instr(&alu2->src[src2].src);