bugreport: fix warning.

The command the warning wants you to use instead is "bugreportz", not
"bugreport". You're already running bugreport!

...unless you're on the host and you're running `adb bugreport` which
silently uses bugreportz behind the scenes. No wonder humans are
confused!

Also error out if given any arguments, since no arguments are supported.

Bug: http://b/156667896
Bug: http://b/29448020
Test: adb shell bugreport
Test: adb shell bugreport --help
Change-Id: Ia141e89eb5019d52247f57c5095288e96f57dccd
diff --git a/cmds/bugreport/bugreport.cpp b/cmds/bugreport/bugreport.cpp
index 840ae47..258b367 100644
--- a/cmds/bugreport/bugreport.cpp
+++ b/cmds/bugreport/bugreport.cpp
@@ -27,12 +27,19 @@
 // dumpstate, then connect to the dumpstate local client to read the
 // output. All of the dumpstate output is written to stdout, including
 // any errors encountered while reading/writing the output.
-int main() {
-
+int main(int argc, char* /*argv*/[]) {
   fprintf(stderr, "=============================================================================\n");
-  fprintf(stderr, "WARNING: flat bugreports are deprecated, use adb bugreport <zip_file> instead\n");
+  fprintf(stderr, "WARNING: Flat (text file, non-zipped) bugreports are deprecated.\n");
+  fprintf(stderr, "WARNING: Please generate zipped bugreports instead.\n");
+  fprintf(stderr, "WARNING: On the host use: adb bugreport filename.zip\n");
+  fprintf(stderr, "WARNING: On the device use: bugreportz filename.zip\n");
   fprintf(stderr, "=============================================================================\n\n\n");
 
+  if (argc != 1) {
+    fprintf(stderr, "usage: bugreport\n");
+    exit(1);
+  }
+
   // Start the dumpstate service.
   property_set("ctl.start", "dumpstate");