Prune some unused compile definitions

There's a lot of unnecessary system configuration junk here which
isn't used, and is already available through compiler predefines. This
is also blindly placed without really checking the host architecture.

-DLINUX is unused.

-D__AMD64__ is predefined by the compiler, and is also redundant with
 __x86_64__ and ATI_BITS_64.

__x86_64__ should also be removed. It's used in libelf, but I'm not
sure if msvc predefines this or not.

-DqLittleEndian is unused, and also doesn't follow macro naming
 conventions (plus compilers have their own predefines for checking
 this).

Change-Id: I89f6fc4c88e861623be7f32df41aecbb4e9009ab

rocclr/CMakeLists.txt

@@ -55,7 +55,7 @@ set(CMAKE_CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_EXTENSIONS OFF)
 set(CMAKE_POSITION_INDEPENDENT_CODE ON)
 
-add_definitions(-DLINUX -D__x86_64__ -D__AMD64__ -DUNIX_OS -DqLittleEndian -DOPENCL_MAJOR=2 -DOPENCL_MINOR=1 -DCL_TARGET_OPENCL_VERSION=220 -DWITH_AQL -DWITH_ONLINE_COMPILER -DATI_OS_LINUX -DATI_ARCH_X86 -DLITTLEENDIAN_CPU -DATI_BITS_64 -DATI_COMP_GCC -DWITH_TARGET_AMDGCN -DOPENCL_EXPORTS -DCL_USE_DEPRECATED_OPENCL_1_0_APIS -DCL_USE_DEPRECATED_OPENCL_1_1_APIS -DCL_USE_DEPRECATED_OPENCL_1_2_APIS -DCL_USE_DEPRECATED_OPENCL_2_0_APIS -DVEGA10_ONLY=false -DWITH_LIGHTNING_COMPILER)
+add_definitions(-D__x86_64__ -DOPENCL_MAJOR=2 -DOPENCL_MINOR=1 -DCL_TARGET_OPENCL_VERSION=220 -DATI_OS_LINUX -DATI_ARCH_X86 -DLITTLEENDIAN_CPU -DATI_BITS_64 -DWITH_TARGET_AMDGCN -DOPENCL_EXPORTS -DCL_USE_DEPRECATED_OPENCL_1_0_APIS -DCL_USE_DEPRECATED_OPENCL_1_1_APIS -DCL_USE_DEPRECATED_OPENCL_1_2_APIS -DCL_USE_DEPRECATED_OPENCL_2_0_APIS -DVEGA10_ONLY=false -DWITH_LIGHTNING_COMPILER)
 add_definitions(-DOPENCL_C_MAJOR=2 -DOPENCL_C_MINOR=0)
 
 set(CMAKE_SHARED_LINKER_FLAGS "-Wl,-Bsymbolic -Wl,--unresolved-symbols=report-all")