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>
diff --git a/arch/um/sys-ppc/miscthings.c b/arch/um/sys-ppc/miscthings.c
index 1c11aed..25908d2 100644
--- a/arch/um/sys-ppc/miscthings.c
+++ b/arch/um/sys-ppc/miscthings.c
@@ -1,6 +1,6 @@
-#include "linux/threads.h"
-#include "linux/stddef.h"  // for NULL
-#include "linux/elf.h"  // for AT_NULL
+#include <linux/threads.h>
+#include <linux/stddef.h>  // for NULL
+#include <linux/elf.h>  // for AT_NULL
 
 /* The following function nicked from arch/ppc/kernel/process.c and
  * adapted slightly */