fastboot: remove command queue

There is little advantage and increasingly much disadvantage to
queueing up fastboot commands before executing them.  This change
removes the queue in the most simple way possible to enable further
clean up.

Test: fastboot works
Change-Id: I9abab05df07ed167dbe6a42e1eb9eab8f8d4f157
diff --git a/fastboot/util.h b/fastboot/util.h
index 9033f93..20be461 100644
--- a/fastboot/util.h
+++ b/fastboot/util.h
@@ -12,6 +12,8 @@
 char* xstrdup(const char*);
 void set_verbose();
 
+void Status(const std::string& message);
+
 // These printf-like functions are implemented in terms of vsnprintf, so they
 // use the same attribute for compile-time format string checking.
 void die(const char* fmt, ...) __attribute__((__noreturn__))