Make GetShortInt available with WOLFSSL_ASN_EXTRA

Customers may need to use GetShortInt when doing custom ASN.1 parsing.
Was only available when !NO_PWDBASED.
GetShortInt is still an internal API.

wolfcrypt/src/asn.c

@@ -105,6 +105,8 @@ ASN Options:
  * WOLFSSL_ECC_SIGALG_PARAMS_NULL_ALLOWED: Allows the ECDSA/EdDSA signature
  *  algorithms in certificates to have NULL parameter instead of empty.
  *  DO NOT enable this unless required for interoperability.
+ * WOLFSSL_ASN_EXTRA: Make more ASN.1 APIs available regardless of internal
+ *  usage.
 */
 
 #include <wolfssl/wolfcrypt/error-crypt.h>
@@ -3176,7 +3178,7 @@ int GetMyVersion(const byte* input, word32* inOutIdx,
 }
 
 
-#ifndef NO_PWDBASED
+#if !defined(NO_PWDBASED) || defined(WOLFSSL_ASN_EXTRA)
 /* Decode small integer, 32 bits or less.
  *
  * @param [in]      input     Buffer of BER data.
@@ -3241,8 +3243,10 @@ int GetShortInt(const byte* input, word32* inOutIdx, int* number, word32 maxIdx)
     return ret;
 #endif
 }
+#endif /* !NO_PWDBASED || WOLFSSL_ASN_EXTRA */
 
 
+#ifndef NO_PWDBASED
 #if !defined(WOLFSSL_ASN_TEMPLATE) || defined(HAVE_PKCS8) || \
      defined(HAVE_PKCS12)
 /* Set small integer, 32 bits or less. DER encoding with no leading 0s