Add missing includes.

Change-Id: I06ea08400efa511e627be37a4fd70fbdfadea2e6
diff --git a/applypatch/imgpatch.c b/applypatch/imgpatch.c
index 33c4487..09b0a73 100644
--- a/applypatch/imgpatch.c
+++ b/applypatch/imgpatch.c
@@ -21,6 +21,7 @@
 #include <sys/cdefs.h>
 #include <sys/stat.h>
 #include <errno.h>
+#include <malloc.h>
 #include <unistd.h>
 #include <string.h>