Refactor libfastboot

This change creates a nice and clean API for issuing
fastboot commands without using the fastboot tool itself.

Test: fastboot tool itself (now using libfastboot2)
on sailfish, walleye, and other devices.
Test: flash bootloader bootloader.img
Test: flash radio radio.img
Test: -w update img.zip
Test: Manually getvar and reboot commands.

Bug: 111126621
Change-Id: I0022536b204ce0c5ad8329367fd522fa3c57877d
diff --git a/fastboot/usb_linux.cpp b/fastboot/usb_linux.cpp
index cdab4f1..386dd30 100644
--- a/fastboot/usb_linux.cpp
+++ b/fastboot/usb_linux.cpp
@@ -47,8 +47,8 @@
 #include <memory>
 #include <thread>
 
-#include "fastboot.h"
 #include "usb.h"
+#include "util.h"
 
 using namespace std::chrono_literals;