uboot-envtools: move to Boot Loaders submenu

Boot Loaders submenu is where other bootloader tools (fconfig and grub2-editenv) are.

Signed-off-by: Alberto Bursi <alberto.bursi@outlook.it>

package/boot/uboot-envtools/Makefile

@@ -31,6 +31,7 @@ include $(INCLUDE_DIR)/package.mk
 define Package/uboot-envtools
   SECTION:=utils
   CATEGORY:=Utilities
+  SUBMENU:=Boot Loaders
   TITLE:=read/modify U-Boot bootloader environment
   URL:=http://www.denx.de/wiki/U-Boot
 endef