test/timing_load_creds.c: Add fclose() if error occurs

Add fclose() if error occurs to release fp.

Fixes: 6212fc6814 ("Add a stand-alone "timing" program")
Signed-off-by: Jiasheng Jiang <jiashengjiangcool@gmail.com>

Reviewed-by: Kurt Roeckx <kurt@roeckx.be>
Reviewed-by: Paul Dale <ppzgs1@gmail.com>
(Merged from https://github.com/openssl/openssl/pull/28007)

test/timing_load_creds.c

@@ -150,6 +150,7 @@ int main(int ac, char **av)
     }
     fp = fopen(av[0], "r");
     if ((long)fread(contents, 1, sb.st_size, fp) != sb.st_size) {
+        fclose(fp);
         OPENSSL_free(contents);
         perror("fread");
         exit(EXIT_FAILURE);