staging: rtl8188eu: fix typo in comment

Fix typo in the words 'transmitted' and 'failure' in the comment. Issue
found using checkpatch.

Signed-off-by: Santha Meena Ramamoorthy <santhameena13@gmail.com>
Reviewed-by: Vaishali Thakkar <vthakkar@vaishalithakkar.in>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>