um: get rid of pointless include "..." where include <...> will do

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Richard Weinberger <richard@nod.at>

arch/um/kernel/time.c

@@ -10,8 +10,8 @@
 #include <linux/threads.h>
 #include <asm/irq.h>
 #include <asm/param.h>
-#include "kern_util.h"
-#include "os.h"
+#include <kern_util.h>
+#include <os.h>
 
 void timer_handler(int sig, struct siginfo *unused_si, struct uml_pt_regs *regs)
 {