Revert "PCI: loongson: Prevent LS7A MRRS increases"

This reverts commit 654ae539 which is
commit 8b3517f8 upstream.

It breaks the Android kernel abi and it not needed for any Android
devices at this time.  If it is needed, it can be brought back in an
ABI-safe way.

Bug: 161946584
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
Change-Id: I8543def5fb03133f4772ba1976f882d182bba677