Print a message when simulating CPUs.

Make it more obvious something is happening.

Change-Id: Ie68d1e96a9bedd4b572c1cc99910348f89f07624
Reviewed-on: https://boringssl-review.googlesource.com/c/33244
Commit-Queue: Adam Langley <agl@google.com>
Reviewed-by: Adam Langley <agl@google.com>
CQ-Verified: CQ bot account: commit-bot@chromium.org <commit-bot@chromium.org>

crypto/test/gtest_main.cc

@@ -65,6 +65,7 @@ int main(int argc, char **argv) {
                 cpu);
         exit(89);
       }
+      printf("Simulating CPU '%s'\n", cpu);
       *armcap_ptr = armcap;
     }
   }