[UR] Provide flexibility to replace unified-memory-framework repo and tag

Author: againull

source/common/CMakeLists.txt

@@ -20,11 +20,14 @@ target_include_directories(ur_common PUBLIC
 )
 
 message(STATUS "Download Unified Memory Framework from github.com")
+if (NOT DEFINED UMF_REPO)
+    set(UMF_REPO "https://github.com/oneapi-src/unified-memory-framework.git")
+endif()
 
-set(UMF_REPO "https://github.com/oneapi-src/unified-memory-framework.git")
-
-# Merge pull request #119 from ldorau/Fix_arena_extent_split_and_arena_extent_merge
-set(UMF_TAG 9bf7a0dc4dff76844e10edbb5c6e9d917536ef6d)
+if (NOT DEFINED UMF_TAG)
+    # Merge pull request #119 from ldorau/Fix_arena_extent_split_and_arena_extent_merge
+    set(UMF_TAG 9bf7a0dc4dff76844e10edbb5c6e9d917536ef6d)
+endif()
 
 message(STATUS "Will fetch Unified Memory Framework from ${UMF_REPO}")