x86/amd_nb: Add support for newer PCI topologies

x86/amd_nb: Add support for newer PCI topologies

BugLink: https://bugs.launchpad.net/bugs/1819485
Add support for new processors which have multiple PCI root complexes
per data fabric/system management network interface.  If there are (N)
multiple PCI roots per DF/SMN interface, then the PCI roots are
redundant (as far as SMN/DF access goes).  For each DF/SMN interface:
map to the first available PCI root and skip the next N-1 PCI roots so
the following DF/SMN interface get mapped to a correct PCI root.

Ex:
DF/SMN 0 -> 60
	    40
	    20
	    00
DF/SMN 1 -> e0
	    c0
	    a0
	    80

Signed-off-by: Brian Woods <brian.woods@amd.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
CC: Bjorn Helgaas <bhelgaas@google.com>
CC: Clemens Ladisch <clemens@ladisch.de>
CC: Guenter Roeck <linux@roeck-us.net>
CC: "H. Peter Anvin" <hpa@zytor.com>
CC: Ingo Molnar <mingo@redhat.com>
CC: Jean Delvare <jdelvare@suse.com>
CC: Jia Zhang <qianyue.zj@alibaba-inc.com>
CC: <linux-hwmon@vger.kernel.org>
CC: <linux-pci@vger.kernel.org>
CC: Pu Wen <puwen@hygon.cn>
CC: Thomas Gleixner <tglx@linutronix.de>
CC: x86-ml <x86@kernel.org>
Link: http://lkml.kernel.org/r/20181106200754.60722-3-brian.woods@amd.com
(backported from commit 556e4c62baffa71e2045a298379db7e57dd47f3d)
Signed-off-by: Andrea Righi <andrea.righi@canonical.com>
Acked-by: Khalid Elmously <khalid.elmously@canonical.com>
Acked-by: Connor Kuehl <connor.kuehl@canonical.com>
Signed-off-by: Khalid Elmously <khalid.elmously@canonical.com>