Staging: rtlwifi: remove unnecessary NULL check

The member regd of the struct rtl_priv is true in a boolean context.

drivers/staging/rtlwifi/regd.c:413:27: warning: address of 'rtlpriv->regd' will always
      evaluate to 'true' [-Wpointer-bool-conversion]
        if (!wiphy || !&rtlpriv->regd)
                      ~ ~~~~~~~~~^~~~
1 warning generated.

Link: https://github.com/ClangBuiltLinux/linux/issues/170



Signed-off-by: Karthik Nishanth <nishanthkarthik@live.com>
Reviewed-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>