[FL-2554] Embedded arm-none-eabi toolchain (#1351)

fbt.cmd

@@ -1,15 +1,17 @@
 @echo off
+call %~dp0scripts\toolchain\fbtenv.cmd env
 
 set SCONS_EP=%~dp0\lib\scons\scripts\scons.py
 
 if [%FBT_NO_SYNC%] == [] (
-	if exist ".git" (
-		git submodule update --init
-	) else (
-		echo Not in a git repo, please clone with git clone --recursive
-		exit /b 1
-	)
+    if exist ".git" (
+        git submodule update --init
+    ) else (
+        echo Not in a git repo, please clone with git clone --recursive
+        exit /b 1
+    )
 )
+git submodule update --init
 
 set "SCONS_DEFAULT_FLAGS=-Q --warn=target-not-built"
-python %SCONS_EP% %SCONS_DEFAULT_FLAGS% %*
+python lib\scons\scripts\scons.py %SCONS_DEFAULT_FLAGS% %*