x86 wants to get rid of the global pci_lock protecting the config space
accessors so ECAM mode can operate completely lockless, but the CE4100 PCI
code relies on that to protect the simulation registers.

Restructure the code so it uses the x86 specific pci_config_lock to
serialize the inner workings of the CE4100 PCI magic. That allows to remove
the global locking via pci_lock later.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Acked-by: NBjorn Helgaas <helgaas@kernel.org>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: linux-pci@vger.kernel.org
Link: http://lkml.kernel.org/r/20170316215057.126873574@linutronix.deSigned-off-by: NThomas Gleixner <tglx@linutronix.de>