common: Drop flash.h from common header

Move this uncommon header out of the common header.

Fix up some style problems in flash.h while we are here.

Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/common/board_r.c b/common/board_r.c
index 96034b8..bd074eb 100644
--- a/common/board_r.c
+++ b/common/board_r.c
@@ -13,6 +13,7 @@
 #include <api.h>
 #include <cpu_func.h>
 #include <exports.h>
+#include <flash.h>
 #include <hang.h>
 #include <image.h>
 #include <irq_func.h>
diff --git a/common/flash.c b/common/flash.c
index 9601716..4a28ac5 100644
--- a/common/flash.c
+++ b/common/flash.c
@@ -8,6 +8,7 @@
 
 #include <common.h>
 #include <flash.h>
+#include <uuid.h>
 
 #include <mtd/cfi_flash.h>