CMakeLists: Use pkgconfig more effectively with DRM_DIR

Instead of hard-coding lib64 and other include locations, just prepend
the DRM_DIR to the beginning of the CMake prefix path. Then let
pkgconfig find the package, the same way that it would if DRM_DIR wasn't
set. DRM_DIR takes precedence, but the default paths will be used if
DRM_DIR isn't set, or doesn't point to where libdrm is housed

Note that /lib and /lib/$ARCH aren't required for DRM_DIR, just the
path to the root folder for the package (e.g. /opt/amdgpu instead of
/opt/amdgpu/lib or /opt/amdgpu/lib64 or /opt/amdgpu/lib/x86_64-linux-gnu
etc)

Change-Id: I56767db28476d14e3fa77be1089c3904e2a32450

CMakeLists.txt

@@ -166,20 +166,13 @@ message(STATUS "NUMA:" ${NUMA})
 
 ## If environment variable DRM_DIR is set, the script
 ## will pick up the corresponding libraries from that path.
-if( DEFINED ENV{DRM_DIR} )
-#assume header files and libraries are under the same path
-    set ( DRM_DIR $ENV{DRM_DIR} )
-    set ( DRM_INCLUDE_DIRS ${DRM_DIR}/include )
-    link_directories(${DRM_DIR}/lib64)
-    set ( DRM_LIBRARIES drm )
-    set ( DRM_AMDGPU_LIBRARIES drm_amdgpu )
-else()
+list (PREPEND CMAKE_PREFIX_PATH "${DRM_DIR}")
+
 # The module name passed to pkg_check_modules() is determined by the
 # name of file *.pc
-    pkg_check_modules(DRM REQUIRED libdrm)
-    pkg_check_modules(DRM_AMDGPU REQUIRED libdrm_amdgpu)
-    include_directories(${DRM_AMDGPU_INCLUDE_DIRS})
-endif()
+pkg_check_modules(DRM REQUIRED libdrm)
+pkg_check_modules(DRM_AMDGPU REQUIRED libdrm_amdgpu)
+include_directories(${DRM_AMDGPU_INCLUDE_DIRS})
 include_directories(${DRM_INCLUDE_DIRS})
 
 target_link_libraries ( ${HSAKMT_TARGET}

tests/kfdtest/CMakeLists.txt

@@ -92,20 +92,12 @@ set (CPACK_RPM_PACKAGE_REQUIRES "rocm-core")
 
 find_package(PkgConfig)
 
-if( DEFINED ENV{DRM_DIR} )
-#assume header files and libraries are under the same path
-    set ( DRM_DIR $ENV{DRM_DIR} )
-    set ( DRM_INCLUDE_DIRS ${DRM_DIR}/include )
-    link_directories(${DRM_DIR}/lib64)
-    set ( DRM_LIBRARIES drm )
-    set ( DRM_AMDGPU_LIBRARIES drm_amdgpu )
-else()
+list (PREPEND CMAKE_PREFIX_PATH "${DRM_DIR}")
 # The module name passed to pkg_check_modules() is determined by the
 # name of file *.pc
-    pkg_check_modules(DRM REQUIRED libdrm)
-    pkg_check_modules(DRM_AMDGPU REQUIRED libdrm_amdgpu)
-    include_directories(${DRM_AMDGPU_INCLUDE_DIRS})
-endif()
+pkg_check_modules(DRM REQUIRED libdrm)
+pkg_check_modules(DRM_AMDGPU REQUIRED libdrm_amdgpu)
+include_directories(${DRM_AMDGPU_INCLUDE_DIRS})
 
 if( DEFINED ENV{LIBHSAKMT_PATH} )
     set ( LIBHSAKMT_PATH $ENV{LIBHSAKMT_PATH} )