[SWDEV-528647/SWDEV-528450] Reduce API load times and libdrm/libdrm_amdgpu dynamic loading (#333)

Changes:
- Removed libdrm/libdrm_amdgpu dependencies
- Added/updated new internal libdrm/libdrm_amdgpu/xf86drm APIs
  to allow our APIs to reference before dynamic loading
  the libdrm/libdrm_amdgpu libraries:
  1. amdgpu_drm.h to what's seen in mainline
  2. Added xf86drm.h to whats seen in mainline
- Modified internal DRM capabilities:
  1. Require each API to independently connect to libdrm/libdrm_amdgpu
     + validate API handles reponses accordingly
  2. Initialization of AMD SMI no longer has as strong of a tie to
     libdrm
- Updated internal implementations of several APIs which have
connections to libdrm/libdrm_amdgpu or APIs which have conflicts
with open libdrm/libdrm_amdgpu connections:
  1. amdsmi_init()
  2. amdsmi_get_gpu_vram_usage()
  3. amdsmi_get_gpu_asic_info()
  4. amdsmi_get_gpu_vram_info()
  5. amdsmi_get_gpu_vbios_info()
  6. amdsmi_get_gpu_driver_info()
  7. amdsmi_get_gpu_virtualization_mode()
  8. amdsmi_set_gpu_memory_partition()
  9. amdsmi_set_gpu_memory_partition_mode()
- Cleaned up effected tests/APIs

Change-Id: I96e2cf1b06b0cfee1b01a5e991ccc6116c4245a8

README.md

@@ -169,7 +169,7 @@ This section describes the prerequisites and steps to build AMD SMI from source.
 To build the AMD SMI library, the following components are required. Note that the software versions specified were used
 during development; earlier versions are not guaranteed to work.
 
-* CMake (v3.14.0 or later) -- `python3 -m pip install cmake`
+* CMake (v3.15.0 or later) -- `python3 -m pip install cmake`
 * g++ (v5.4.0 or later)
 * libdrm-dev (for Ubuntu and Debian)
 * libdrm-devel (for RPM-based distributions)