Uboot bootstate (#215)

* Uboot: cleaning up bootstate env import/export.

* Tinker: Add potential eMMC boot support.

buildroot-external/board/asus/tinker/patches/uboot/0001-Support-HassOS-bootstate-partition.patch

@@ -1,29 +0,0 @@
-From 8458beb24f2540fff3c3faed4fa068553b9e474e Mon Sep 17 00:00:00 2001
-From: Pascal Vizeli <pvizeli@syshack.ch>
-Date: Wed, 8 Aug 2018 09:45:07 +0000
-Subject: [PATCH 1/1] Support HassOS bootstate partition
-
-Signed-off-by: Pascal Vizeli <pvizeli@syshack.ch>
----
- env/mmc.c | 5 +++++
- 1 file changed, 5 insertions(+)
-
-diff --git a/env/mmc.c b/env/mmc.c
-index 5e3da6dca75..353f58a12c9 100644
---- a/env/mmc.c
-+++ b/env/mmc.c
-@@ -18,6 +18,11 @@
- #include <search.h>
- #include <errno.h>
- 
-+#undef CONFIG_SYS_MMC_ENV_DEV
-+#define CONFIG_SYS_MMC_ENV_DEV 1
-+#undef CONFIG_ENV_OFFSET
-+#define CONFIG_ENV_OFFSET 0x25100000
-+
- #define __STR(X) #X
- #define STR(X) __STR(X)
- 
--- 
-2.17.1
-