staging: rtl8723bs: Fix dereference before check warning in os_dep/recv_linux.c

Smatch lists the following warning:

  CHECK   drivers/staging/rtl8723bs/os_dep/recv_linux.c
drivers/staging/rtl8723bs/os_dep/recv_linux.c:353 rtw_recv_indicatepkt() warn: variable dereferenced before check 'precv_frame' (see line 312)

This warning is fixed by removing the test at line 353.

Signed-off-by: Larry Finger <Larry.Finger@lwfinger.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>