[LLVM][CMake][NFC] Resolve FIXME: Rename LLVM_CMAKE_PATH to LLVM_CMAKE_DIR throughout the project

This way, we do not need to set LLVM_CMAKE_PATH to LLVM_CMAKE_DIR when (NOT LLVM_CONFIG_FOUND)

Reviewed By: #libc, ldionne

Differential Revision: https://reviews.llvm.org/D107717

GitOrigin-RevId: a2c319fdc6b35ae6d8578459f07c89042775e5ec
diff --git a/CMakeLists.txt b/CMakeLists.txt
index db202a7..16331d9 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -364,6 +364,6 @@
   add_subdirectory(docs)
 endif()
 
-if (LIBUNWIND_INCLUDE_TESTS AND EXISTS ${LLVM_CMAKE_PATH})
+if (LIBUNWIND_INCLUDE_TESTS AND EXISTS ${LLVM_CMAKE_DIR})
   add_subdirectory(test)
 endif()