Add tests for x509parse_key_ec()
Test files were generated as follows:
openssl ecparam -name prime192v1 -genkey > key.pem
openssl ec -in key.pem -pubout -outform PEM > pub.pem
openssl ec -in key.pem -pubout -outform DER > pub.der
openssl ec -in key.pem -outform pem > prv.sec1.pem
openssl ec -in key.pem -outform der > prv.sec1.der
openssl ec -in key.pem -des -passout pass:polar -outform pem > prv.sec1.pw.pem
openssl pkcs8 -topk8 -in key.pem -nocrypt -outform pem > prv.pk8.pem
openssl pkcs8 -topk8 -in key.pem -nocrypt -outform der > prv.pk8.der
openssl pkcs8 -topk8 -in key.pem -passout pass:polar -outform der \
> prv.pk8.pw.der
openssl pkcs8 -topk8 -in key.pem -passout pass:polar -outform pem \
> prv.pk8.pw.pem
diff --git a/tests/data_files/ec_prv.pk8.pem b/tests/data_files/ec_prv.pk8.pem
new file mode 100644
index 0000000..dbeab7c
--- /dev/null
+++ b/tests/data_files/ec_prv.pk8.pem
@@ -0,0 +1,5 @@
+-----BEGIN PRIVATE KEY-----
+MG8CAQAwEwYHKoZIzj0CAQYIKoZIzj0DAQEEVTBTAgEBBBgzjoaogeI49Um9bwVT
+SUtz49YRMP3GyW2hNAMyAARRdbzfMKNw851Tk+YScojYAWe19LS3dsZ098bzVLfS
+JAYsH2hUtaevD+V46vJY8Cc=
+-----END PRIVATE KEY-----