Drop, now unused, KAT value.

Change-Id: Ief328bb2a8b6264226a89233c9fba0e4621de9d7
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/51425
Commit-Queue: Adam Langley <agl@google.com>
Reviewed-by: David Benjamin <davidben@google.com>
Commit-Queue: David Benjamin <davidben@google.com>

crypto/fipsmodule/self_check/self_check.c

diff --git a/crypto/fipsmodule/self_check/self_check.c b/crypto/fipsmodule/self_check/self_check.c
index a43c61d..fe40d90 100644
--- a/crypto/fipsmodule/self_check/self_check.c
+++ b/crypto/fipsmodule/self_check/self_check.c
@@ -585,9 +585,6 @@
   return ret;
 }
 
-static const uint8_t kPlaintext[64] =
-    "BoringCryptoModule FIPS KAT Encryption and Decryption Plaintext!";
-
 int boringssl_self_test_sha256(void) {
   static const uint8_t kInput[16] = {
       0xff, 0x3b, 0x85, 0x7d, 0xa7, 0x23, 0x6a, 0x2b,