ssl->ctx cannot be NULL.

Most code already dereferences it directly.

Change-Id: I227fa91ecbf25a19077f7cfba21b0abd2bc2bd1d
Reviewed-on: https://boringssl-review.googlesource.com/7422
Reviewed-by: David Benjamin <davidben@google.com>

ssl/t1_lib.c

diff --git a/ssl/t1_lib.c b/ssl/t1_lib.c
index 2c9a0b2..8facdd3 100644
--- a/ssl/t1_lib.c
+++ b/ssl/t1_lib.c
@@ -2367,11 +2367,10 @@
   int ret = SSL_TLSEXT_ERR_NOACK;
   int al = SSL_AD_UNRECOGNIZED_NAME;
 
-  if (ssl->ctx != NULL && ssl->ctx->tlsext_servername_callback != 0) {
+  if (ssl->ctx->tlsext_servername_callback != 0) {
     ret = ssl->ctx->tlsext_servername_callback(ssl, &al,
-                                             ssl->ctx->tlsext_servername_arg);
-  } else if (ssl->initial_ctx != NULL &&
-             ssl->initial_ctx->tlsext_servername_callback != 0) {
+                                               ssl->ctx->tlsext_servername_arg);
+  } else if (ssl->initial_ctx->tlsext_servername_callback != 0) {
     ret = ssl->initial_ctx->tlsext_servername_callback(
         ssl, &al, ssl->initial_ctx->tlsext_servername_arg);
   }
@@ -2398,11 +2397,10 @@
   int ret = SSL_TLSEXT_ERR_OK;
   int al = SSL_AD_UNRECOGNIZED_NAME;
 
-  if (ssl->ctx != NULL && ssl->ctx->tlsext_servername_callback != 0) {
+  if (ssl->ctx->tlsext_servername_callback != 0) {
     ret = ssl->ctx->tlsext_servername_callback(ssl, &al,
-                                             ssl->ctx->tlsext_servername_arg);
-  } else if (ssl->initial_ctx != NULL &&
-             ssl->initial_ctx->tlsext_servername_callback != 0) {
+                                               ssl->ctx->tlsext_servername_arg);
+  } else if (ssl->initial_ctx->tlsext_servername_callback != 0) {
     ret = ssl->initial_ctx->tlsext_servername_callback(
         ssl, &al, ssl->initial_ctx->tlsext_servername_arg);
   }