Update fastboot to wipe ext4 partitions before flashing

To prevent false error reports from e2fsck, update fastboot to erase
a partition identified as being ext4 partition before flashing an image
to it.

bug: 7259359

Change-Id: I85e9963aa8247b4b33fdd57f994cdb3ee72b670f
diff --git a/fastboot/fastboot.h b/fastboot/fastboot.h
index b4cf195..c1b2964 100644
--- a/fastboot/fastboot.h
+++ b/fastboot/fastboot.h
@@ -45,7 +45,8 @@
 
 /* engine.c - high level command queue engine */
 int fb_getvar(struct usb_handle *usb, char *response, const char *fmt, ...);
-void fb_queue_flash(const char *ptn, void *data, unsigned sz);;
+int fb_format_supported(usb_handle *usb, const char *partition);
+void fb_queue_flash(const char *ptn, void *data, unsigned sz);
 void fb_queue_flash_sparse(const char *ptn, struct sparse_file *s, unsigned sz);
 void fb_queue_erase(const char *ptn);
 void fb_queue_format(const char *ptn, int skip_if_not_supported);