Remove global variable and use 'pcidev_path_on_root()' to get the base
address of PCIe controller.
TEST=Build pass and boot up to kernel successfully via SSD on Dojo
board, here is the SSD information in boot log:
== NVME IDENTIFY CONTROLLER DATA ==
PCI VID : 0x15b7
PCI SSVID : 0x15b7
SN : 21517J440114
MN : WDC PC SN530 SDBPTPZ-256G-1006
RAB : 0x4
AERL : 0x7
SQES : 0x66
CQES : 0x44
NN : 0x1
Identified NVMe model WDC PC SN530 SDBPTPZ-256G-1006
BUG=b:178565024
Signed-off-by: Jianjun Wang <jianjun.wang@mediatek.com>
Change-Id: Ia41c82a7aa5d6e9d936e242550851cef83afeae9
Reviewed-on: https://review.coreboot.org/c/coreboot/+/62800
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Yu-Ping Wu <yupingso@google.com>