staging: r8188eu: move linked status check from hal to rtw_mlme_ext

staging: r8188eu: move linked status check from hal to rtw_mlme_ext

Move rtl8188e_sreset_linked_status_check from the hal layer into
rtw_mlme_ext.c.

Like the xmit status check, this is a simple function that's only
called from one place.

With this function gone, hal/rtl8188e_sreset.c and
include/rtl8188e_sreset.h are now empty and can be removed.

Signed-off-by: Martin Kaiser <martin@kaiser.cx>
Link: https://lore.kernel.org/r/20211212185833.22000-3-martin@kaiser.cx
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>