wolfssl: update to 3.15.7, fix Makefile

This includes a fix for a medium-level potential cache attack with a
variant of Bleichenbacher’s attack.  Patches were refreshed.
Increased FP_MAX_BITS to allow 4096-bit RSA keys.
Fixed poly1305 build option, and some Makefile updates.

Signed-off-by: Eneas U de Queiroz <cotequeiroz@gmail.com>

package/libs/wolfssl/patches/100-disable-hardening-check.patch

@@ -1,6 +1,6 @@
 --- a/wolfssl/wolfcrypt/settings.h
 +++ b/wolfssl/wolfcrypt/settings.h
-@@ -1624,7 +1624,7 @@ extern void uITRON4_free(void *p) ;
+@@ -1759,7 +1759,7 @@ extern void uITRON4_free(void *p) ;
  #endif
  
  /* warning for not using harden build options (default with ./configure) */
@@ -8,4 +8,4 @@
 +#if 0
      #if (defined(USE_FAST_MATH) && !defined(TFM_TIMING_RESISTANT)) || \
          (defined(HAVE_ECC) && !defined(ECC_TIMING_RESISTANT)) || \
-         (!defined(NO_RSA) && !defined(WC_RSA_BLINDING) && !defined(HAVE_FIPS))
+         (!defined(NO_RSA) && !defined(WC_RSA_BLINDING) && !defined(HAVE_FIPS) && \