test_firmware: remove unnecessary test_fw_mutex in test_dev_config_show_xxx

Remove unnecessary use of test_fw_mutex in test_dev_config_show_xxx
functions that show simple bool, int, and u8.

Signed-off-by: Scott Branden <scott.branden@broadcom.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Luis Chamberlain <mcgrof@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Link: https://lore.kernel.org/r/20200415002517.4328-1-scott.branden@broadcom.com


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>