meson: move tsan-blacklist.txt to build-support with the other build support files

Fixes: 0d46e0e88b ("meson: Add blacklist when compiling with tsan")
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/28996>
(cherry picked from commit 47f6e24ad5)

.pick_status.json

@@ -4,7 +4,7 @@
         "description": "meson: move tsan-blacklist.txt to build-support with the other build support files",
         "nominated": true,
         "nomination_type": 1,
-        "resolution": 0,
+        "resolution": 1,
         "main_sha": null,
         "because_sha": "0d46e0e88bdeb8bfff3b30c65002cc34d3b7ba4e",
         "notes": null

meson.build

@@ -1927,7 +1927,7 @@ if get_option('b_sanitize') == 'thread'
   # meson versions prior to 1.4 will warn "Consider using the built-in option for sanitizers ..." 
   # later on because it only checks whether the option starts with "-fsanitize",
   # but there is no built-in option for adding a blacklist
-  tsan_blacklist = '-fsanitize-blacklist=@0@'.format(join_paths(meson.project_source_root(), 'tsan-blacklist.txt'))
+  tsan_blacklist = '-fsanitize-blacklist=@0@'.format(join_paths(meson.project_source_root(), 'build-support', 'tsan-blacklist.txt'))
   if cc.has_argument(tsan_blacklist)
     pre_args += tsan_blacklist
   else