staging: rtl8188eu: Removed Unnecessary logging

fix the following checkpatch.pl issues:
WARNING: Unnecessary ftrace-like logging - prefer using ftrace

Signed-off-by: Paul McQuade <paulmcquad@gmail.com>
Link: https://lore.kernel.org/r/20210319144206.23439-1-paulmcquad@gmail.com


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