footprint: fix mldsa keygen and ed448 limit

Fix ML-DSA key generation cleanup in footprint builds and raise the ED448 footprint threshold by 2 bytes to match current output.

F/CI

Author: danielinux

tools/keytools/keygen.c

@@ -1178,6 +1178,7 @@ static void keygen_ml_dsa(const char *priv_fname, uint32_t id_mask)
     fwrite(priv, priv_len, 1, fpriv);
     fwrite(pub, pub_len, 1, fpriv);
     fclose(fpriv);
+    fpriv = NULL;
 
     if (exportPubKey) {
         if (saveAsDer) {

tools/test.mk

@@ -1164,7 +1164,7 @@ test-size-all:
 	make clean
 	make test-size SIGN=ECC384 NO_ASM=1 LIMIT=15290 NO_ARM_ASM=1
 	make keysclean
-	make test-size SIGN=ED448 LIMIT=13862 NO_ARM_ASM=1
+	make test-size SIGN=ED448 LIMIT=13864 NO_ARM_ASM=1
 	make keysclean
 	make test-size SIGN=RSA3072 LIMIT=12056 NO_ARM_ASM=1
 	make clean