ARM: dts: msm: Add number of buses to 8084 device tree

Add number of buses to 8084 bus device-tree. This information was
previously obtained by a macro defined in the header file. Making this
change to leverage device-tree. The number of buses is a system wide
information and is added to all fabrics since they can can be probed in
any order

Change-Id: Idcfc4736aec41788335bf60b2973631fb6200f8b
Signed-off-by: Girish Mahadevan <girishm@codeaurora.org>