Refactored system manager driver to be shared across both intel platform

Signed-off-by: Hadi Asyrafi <muhammad.hadi.asyrafi.abdul.halim@intel.com>
Change-Id: Ic4d056c3d15c3152403dc11641c2452770a6162d

Refactor reset manager into intel common platform directory as it can be
shared by both Stratix 10 and Agilex. Register address and field is now
referred through macros.

Signed-off-by: Hadi Asyrafi <muhammad.hadi.asyrafi.abdul.halim@intel.com>
Change-Id: Id6d50f2a2f5a6bd8d6746b84602ac17ec7f6c07a

Pull out handoff driver to intel/soc/ common directory as they can be
shared by both Agilex and Stratix10 platform.

Share platform_def header between both Agilex and Stratix10 and store
platform specific definitions in socfpga_plat_def.h

Signed-off-by: Hadi Asyrafi <muhammad.hadi.asyrafi.abdul.halim@intel.com>
Change-Id: I8eff1afd7ee71704a36a54fad732ede4f557878d