Compiler warnings from hashx on macos/aarch64

These can be fixed during the stabilization periods and isn't blocking for the alpha:

src/ext/equix/hashx/src/compiler_a64.c:152:26: warning: passing 'uint8_t *' (aka 'unsigned char *') to parameter of type 'char *' converts between pointers to integer types where one is of the unique plain 'char' type and the other is not [-Wpointer-sign]
        __builtin___clear_cache(code, pos);
                                ^~~~
src/ext/equix/hashx/src/compiler_a64.c:152:32: warning: passing 'uint8_t *' (aka 'unsigned char *') to parameter of type 'char *' converts between pointers to integer types where one is of the unique plain 'char' type and the other is not [-Wpointer-sign]
        __builtin___clear_cache(code, pos);
                                      ^~~
src/ext/equix/hashx/src/compiler_a64.c:58:20: warning: comparison of integers of different signs: 'int' and 'const size_t' (aka 'const unsigned long') [-Wsign-compare]
        for (int i = 0; i < program->code_size; ++i) {