Remove sk_new_null call.

This entire function is assuming all the STACK_OF(T) types are secretly
the same type, but best to consistently use the sk_ASN1_VALUE_*
wrappers. The raw sk_foo functions are an implementation detail of the
macros and we probably should rename them to be better prefixed (as
upstream did).

Change-Id: I62d910b93ca6be5e1c83ae269c7df6a437ffb316
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/43884
Reviewed-by: Adam Langley <agl@google.com>
diff --git a/crypto/asn1/tasn_dec.c b/crypto/asn1/tasn_dec.c
index 32aba0b..8b3d22d 100644
--- a/crypto/asn1/tasn_dec.c
+++ b/crypto/asn1/tasn_dec.c
@@ -649,7 +649,7 @@
         } else if (ret == -1)
             return -1;
         if (!*val)
-            *val = (ASN1_VALUE *)sk_new_null();
+            *val = (ASN1_VALUE *)sk_ASN1_VALUE_new_null();
         else {
             /*
              * We've got a valid STACK: free up any items present