console: Don't perform test for CON_BRL flag

We don't call braille_register_console() without CON_BRL flag set.
And the _braille_unregister_console() already tests for console to have
CON_BRL flag. No need to repeat this in braille_unregister_console().

Drop the repetitive checks from Braille console driver.

Link: http://lkml.kernel.org/r/20200203133130.11591-1-andriy.shevchenko@linux.intel.com
To: linux-kernel@vger.kernel.org
To: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Signed-off-by: Petr Mladek <pmladek@suse.com>