Revert "PCI: endpoint: Clear secondary (not primary) EPC in pci_epc_remove_epf()"

This reverts commit 3c2a6d4d which is
commit 688d2eb4 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: Ie3855bc8646589ff198399f6c3f80c14f4e05d2a
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>