env: Move env_get() to env.h

Move env_get() over to the new header file.

Acked-by: Joe Hershberger <joe.hershberger@ni.com>
Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/lib/efi_loader/efi_console.c b/lib/efi_loader/efi_console.c
index 6c8229d..d4765af 100644
--- a/lib/efi_loader/efi_console.c
+++ b/lib/efi_loader/efi_console.c
@@ -9,6 +9,7 @@
 #include <charset.h>
 #include <dm/device.h>
 #include <efi_loader.h>
+#include <env.h>
 #include <stdio_dev.h>
 #include <video_console.h>