staging: rtl8192x: Remove use of seq_printf return value
The seq_printf return value, because it's frequently misused,
will eventually be converted to void.
See: commit 1f33c41c03da ("seq_file: Rename seq_overflow() to
seq_has_overflowed() and make public")
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>