[Libtorch] remove abs compiler path (#42729)

ports/libtorch/no-abs-path.patch

@@ -0,0 +1,25 @@
+diff --git a/caffe2/core/macros.h.in b/caffe2/core/macros.h.in
+index 997752ede3..7209b9a63e 100644
+--- a/caffe2/core/macros.h.in	
++++ b/caffe2/core/macros.h.in
+@@ -35,7 +35,7 @@
+ // Useful build settings that are recorded in the compiled binary
+ #define CAFFE2_BUILD_STRINGS { \
+   {"TORCH_VERSION", "${TORCH_VERSION}"}, \
+-  {"CXX_COMPILER", "${CMAKE_CXX_COMPILER}"}, \
++  {"CXX_COMPILER", "${cxx_compiler}"}, \
+   {"CXX_FLAGS", "${CMAKE_CXX_FLAGS}"}, \
+   {"BUILD_TYPE", "${CMAKE_BUILD_TYPE}"}, \
+   {"BLAS_INFO", "${BLAS_INFO}"}, \
+diff --git a/cmake/Codegen.cmake b/cmake/Codegen.cmake
+index 6fa2ab6ea1..07c449c02b 100644
+--- a/cmake/Codegen.cmake	
++++ b/cmake/Codegen.cmake
+@@ -36,6 +36,7 @@ endfunction()
+ ################################################################################
+ 
+ # ---[ Write the macros file
++cmake_path(GET CMAKE_CXX_COMPILER FILENAME cxx_compiler)
+ configure_file(
+     ${CMAKE_CURRENT_LIST_DIR}/../caffe2/core/macros.h.in
+     ${CMAKE_BINARY_DIR}/caffe2/core/macros.h)

ports/libtorch/portfile.cmake

@@ -38,6 +38,7 @@ vcpkg_from_github(
         force-cuda-include.patch
         fix-aten-cutlass.patch
         fix-build-error-with-fmt11.patch
+        no-abs-path.patch
 )
 
 file(REMOVE_RECURSE "${SOURCE_PATH}/caffe2/core/macros.h") # We must use generated header files

ports/libtorch/vcpkg.json

@@ -1,7 +1,7 @@
 {
   "name": "libtorch",
   "version": "2.1.2",
-  "port-version": 7,
+  "port-version": 8,
   "description": "Tensors and Dynamic neural networks in Python with strong GPU acceleration",
   "homepage": "https://pytorch.org/",
   "license": null,

versions/baseline.json

@@ -5238,7 +5238,7 @@
     },
     "libtorch": {
       "baseline": "2.1.2",
-      "port-version": 7
+      "port-version": 8
     },
     "libtorrent": {
       "baseline": "2.0.10",

versions/l-/libtorch.json

@@ -1,5 +1,10 @@
 {
   "versions": [
+    {
+      "git-tree": "d6c80d406232a0bfd3360a40132a69d9f70b972c",
+      "version": "2.1.2",
+      "port-version": 8
+    },
     {
       "git-tree": "e738e2da09a82affc4bf4090d8c672579364231b",
       "version": "2.1.2",