lib/rbtree-test: Include <linux/prandom.h> instead of <linux/random.h>

Substitute the inclusion of <linux/random.h> header with
<linux/prandom.h> to allow the removal of legacy inclusion
of <linux/prandom.h> from <linux/random.h>.

Signed-off-by: Uros Bizjak <ubizjak@gmail.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>

Author: ubizjak

lib/rbtree_test.c

@@ -2,7 +2,7 @@
 #include <linux/module.h>
 #include <linux/moduleparam.h>
 #include <linux/rbtree_augmented.h>
-#include <linux/random.h>
+#include <linux/prandom.h>
 #include <linux/slab.h>
 #include <asm/timex.h>