staging: rtl8712: fix boundary condition for n

Now that snprintf is replaced by scnprintf n >= MAX_WPA_IE_LEN doesn't
make sense as the maximum value n can take is MAX_WPA_IE_LEN.

Signed-off-by: Rohit Sarkar <rohitsarkar5398@gmail.com>
Reviewed-by: Dan Carpenter <dan.carpenter@oracle.com>
Link: https://lore.kernel.org/r/20191002170518.GA1688@SARKAR


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