metal : refactor + optimize v2 (#15995)

* metal : improve naming

* metal : refactor device

ggml-ci

* cont : props

ggml-ci

* metal : apply ggml_mem_ranges_t

ggml-ci

* metal : remove GGML_METAL_USE_BF16

ggml-ci

* metal : refactor device buffer

ggml-ci

* cont : fix naming

* metal : sync before destroying the backend

ggml-ci

* metal : refactor context

ggml-ci

* metal : migrate ggml-metal.m to ggml-metal.cpp

ggml-ci

* metal : adjust ops API

ggml-ci

* metal : use C++ to store piplienes

ggml-ci

* metal : migrate ops to separate functions

ggml-ci

* metal : add ggml_metal_library_t

ggml-ci

* metal : improve naming

ggml-ci

* metal : cleanp

ggml-ci

* metal : add support for GGML_OP_LOG

ggml-ci

* metal : fix error handling

ggml-ci

ggml/src/ggml-metal/CMakeLists.txt

@@ -5,8 +5,12 @@ find_library(METALKIT_FRAMEWORK MetalKit   REQUIRED)
 message(STATUS "Metal framework found")
 
 ggml_add_backend_library(ggml-metal
-                         ggml-metal.m
+                         ggml-metal.cpp
+                         ggml-metal-device.m
+                         ggml-metal-device.cpp
                          ggml-metal-common.cpp
+                         ggml-metal-context.m
+                         ggml-metal-ops.cpp
                         )
 
 target_link_libraries(ggml-metal PRIVATE
@@ -19,10 +23,6 @@ if (GGML_METAL_NDEBUG)
     add_compile_definitions(GGML_METAL_NDEBUG)
 endif()
 
-if (GGML_METAL_USE_BF16)
-    add_compile_definitions(GGML_METAL_USE_BF16)
-endif()
-
 # copy metal files to bin directory
 configure_file(../ggml-common.h  ${CMAKE_RUNTIME_OUTPUT_DIRECTORY}/ggml-common.h     COPYONLY)
 configure_file(ggml-metal.metal  ${CMAKE_RUNTIME_OUTPUT_DIRECTORY}/ggml-metal.metal  COPYONLY)