chore: fix clippy warnings on const arrays

There is nothing wrong here in the codegen, but align with what clippy
wants to remove the warning.

src/util.rs

@@ -1,4 +1,4 @@
-const TOPVAL: [u32; 170] = [
+static TOPVAL: [u32; 170] = [
     1, 2, 3, 5, 7, 11, 17, 25, 38, 57, 86, 129, 194, 291, 437, 656, 854, 1110, 1443, 1876, 2439,
     3171, 3475, 3823, 4205, 4626, 5088, 5597, 6157, 6772, 7450, 8195, 9014, 9916, 10907, 11998,
     13198, 14518, 15970, 17567, 19323, 21256, 23382, 25720, 28292, 31121, 34233, 37656, 41422,
@@ -70,7 +70,7 @@ pub fn h_distance(x: &[u8], y: &[u8]) -> i32 {
 }
 
 #[cfg(feature = "diff")]
-const BIT_PAIRS_DIFF_TABLE: [[u8; 256]; 256] = {
+static BIT_PAIRS_DIFF_TABLE: [[u8; 256]; 256] = {
     let diff_table: [[u8; 4]; 4] = [[0, 1, 2, 6], [1, 0, 1, 2], [2, 1, 0, 1], [6, 2, 1, 0]];
     let mut table = [[0; 256]; 256];
     let mut i = 0;