msm: pcie: Add support for two RCs

Add the support for two PCIe Root Complexes (RCs) in PCIe driver.
Two RCs have the same bus number but are distinguished by
different domain numbers. Add the rc index number to the msm PCIe
device data structure so that rc index number is not explicit as a
parameter of functions. The enumeration of RC1 can happen either
during bootup or after bootup when WAKE GPIO is asserted by
Endpoint. Thus, add the support to enumerate the device based on
WAKE IRQ as well. The PCIe logging is also updated to support two
RCs.

Change-Id: I7fa46400166c40bdf9e73a1507a559a9526d8aac
Signed-off-by: Yan He <yanhe@codeaurora.org>