In a few places we were passing a variable to pr_buf() for the format
string - oops.
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
                if (flags & OPT_SHOW_FULL_LIST)
                        bch2_string_opt_to_text(out, opt->choices, v);
                else
-                       pr_buf(out, opt->choices[v]);
+                       pr_buf(out, "%s", opt->choices[v]);
                break;
        case BCH_OPT_FN:
                opt->to_text(out, c, sb, v);
 
        char uuid_str[40];
 
        uuid_unparse_lower(uuid, uuid_str);
-       pr_buf(out, uuid_str);
+       pr_buf(out, "%s", uuid_str);
 }
 
 int bch2_strtoint_h(const char *, int *);