bus: brcmstb_gisb: Remove print of base address

Since commit ad67b74d ("printk: hash addresses printed with %p")
pointers are being hashed when printed. Displaying the virtual memory at
bootup time is not helpful, especially given we use a dev_info() which
already displays the platform device's address.

Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>