Fix fastbootd's <linux/kexec.h> reference.

Change-Id: I28ce0288a6377153a96d3a98d6913d1271e3112f
diff --git a/fastbootd/commands/boot.h b/fastbootd/commands/boot.h
index bfbf1de..901c38a 100644
--- a/fastbootd/commands/boot.h
+++ b/fastbootd/commands/boot.h
@@ -33,12 +33,10 @@
 #define __FASTBOOT_BOOT_H
 
 #include <sys/cdefs.h>
-#include <uapi/linux/kexec.h>
+#include <linux/kexec.h>
 
 #include "bootimg.h"
 
-#define KEXEC_SEGMENT_MAX 16
-
 #define KEXEC_TYPE_DEFAULT 0
 #define KEXEC_TYPE_CRASH   1