Kernel: add is_tty() to inode

kernel/include/kernel/FS/Inode.h

@@ -77,6 +77,7 @@ namespace Kernel
 
 		virtual bool is_device() const { return false; }
 		virtual bool is_pipe() const { return false; }
+		virtual bool is_tty() const { return false; }
 
 		virtual BAN::ErrorOr<BAN::String> link_target() { ASSERT_NOT_REACHED(); }
 

kernel/include/kernel/Terminal/TTY.h

@@ -109,6 +109,7 @@ namespace Kernel
 
 	public:
 		virtual dev_t rdev() const override { return m_rdev; }
+		virtual bool is_tty() const override { return true; }
 
 	private:
 		dev_t m_rdev;