fbt: lint fixes (#2008)

* lint: exclude "lib" subfolder from naming checks; fbt: moved LINT_SOURCES from literal strings to Dir() nodes
* lint: also exclude hidden directories

Co-authored-by: あく <alleteam@gmail.com>

lib/nfc/SConscript

@@ -5,7 +5,7 @@ env.Append(
         "#/lib/nfc",
     ],
     SDK_HEADERS=[
-        File("#/lib/nfc/nfc_device.h"),
+        File("nfc_device.h"),
     ],
 )