Revert "tcp: add receive queue awareness in tcp_rcv_space_adjust()"

This reverts commit 84c156a3 which is
commit ea33537d upstream.

It breaks the Android kernel abi and can be brought back in the future
in an abi-safe way if it is really needed.

Bug: 161946584
Change-Id: I438e7a8dcf78ccb7c402de534598663642cb2fc3
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>