rtlwifi: use true,false for bool variable in rtl_init_rfkill()

The 'blocked' is a bool variable, and '==' expression itself is bool
too. So no need to convert it to 0/1.

This fixes the following coccicheck warning:

drivers/net/wireless/realtek/rtlwifi/base.c:508:13-41: WARNING:
Comparison of 0/1 to bool variable

Signed-off-by: Jason Yan <yanaijie@huawei.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/20200426094115.23294-1-yanaijie@huawei.com