hardware/allwinner: Fix build with environment outside mmc

modules/hardware/allwinner/0001-sunxi-Use-mmc_get_env_dev-only-if-relevant.patch

@@ -0,0 +1,34 @@
+From 30da7f7745f15ead3a5bbc7e99a421bdb9009855 Mon Sep 17 00:00:00 2001
+From: Samuel Dionne-Riel <[email protected]>
+Date: Tue, 22 Feb 2022 10:51:33 -0500
+Subject: [PATCH] sunxi: Use mmc_get_env_dev only if relevant
+
+When build is made with environment elsewhere than on MMC, the reference
+to `CONFIG_SYS_MMC_ENV_DEV` will not exist, and thus this fails.
+---
+ board/sunxi/board.c | 2 ++
+ 1 file changed, 2 insertions(+)
+
+diff --git a/board/sunxi/board.c b/board/sunxi/board.c
+index 1a46100e408..689034355e8 100644
+--- a/board/sunxi/board.c
++++ b/board/sunxi/board.c
+@@ -637,6 +637,7 @@ int board_mmc_init(struct bd_info *bis)
+ 	return 0;
+ }
+
++#ifdef CONFIG_SYS_MMC_ENV_DEV
+ #if CONFIG_MMC_SUNXI_SLOT_EXTRA != -1
+ int mmc_get_env_dev(void)
+ {
+@@ -651,6 +652,7 @@ int mmc_get_env_dev(void)
+ }
+ #endif
+ #endif
++#endif
+
+ #ifdef CONFIG_SPL_BUILD
+
+-- 
+2.34.0
+

modules/hardware/allwinner/default.nix

@@ -79,6 +79,9 @@ in
           mmc bootbus ${mmcBootIndex} 1 0 0
           mmc partconf ${mmcBootIndex} 1 1 1
         '';
+        patches = [
+          ./0001-sunxi-Use-mmc_get_env_dev-only-if-relevant.patch
+        ];
       };
     })
     (mkIf (anyAllwinner64) {