rtlwifi: rtl8723be: Fix smatch warnings

Smatch reports the following:

drivers/net/wireless/rtlwifi/rtl8723be/fw.c:208 _rtl8723be_fill_h2c_command() warn: variable dereferenced before check 'rtlhal' (see line 69)
drivers/net/wireless/rtlwifi/rtl8723be/hw.c:1732 _rtl8723be_read_adapter_info() error: __builtin_memcpy() '&rtlefuse->efuse_map[0][0]' too small (256 vs 512)

The first one is fixed by removing two pointless tests for NULL pointers.

Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Larry Finger <Larry.Finger@lwfinger.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>