Typo in EVP_PKEY_asn1_find_str.

Other importing an EC PRIVATE KEY doesn't work.

Change-Id: I58b4e88d287cd7fc772a1958df5878ecff1c5b06
Reviewed-on: https://boringssl-review.googlesource.com/1090
Reviewed-by: Adam Langley <agl@google.com>

crypto/evp/evp.c

@@ -335,7 +335,7 @@ const EVP_PKEY_ASN1_METHOD *EVP_PKEY_asn1_find_str(ENGINE **pengine,
     return &rsa_asn1_meth;
   } else if (len == 4 && memcmp(name, "HMAC", 4) == 0) {
     return &hmac_asn1_meth;
-  } if (len == 2 && memcmp(name, "EC", 4) == 0) {
+  } if (len == 2 && memcmp(name, "EC", 2) == 0) {
     return &ec_asn1_meth;
   }
   return NULL;