staging: rtl8192e: Silence smatch info in r8192E_cmdpkt.c

Smatch outputs the following informational message:

  CHECK   drivers/staging/rtl8192e/r8192E_cmdpkt.c
drivers/staging/rtl8192e/r8192E_cmdpkt.c +419 cmpk_message_handle_rx(77) info: ignoring unreachable code.

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