[tepl] build: don't use join_paths() (deprecated)

[Sébastien Wilmet <swilmet src gnome org>]

commit 319d029566741f62e7136ab096eeeebfcdf0ad0a
Author: Sébastien Wilmet <swilmet gnome org>
Date:   Sun Apr 5 00:33:56 2020 +0200

    build: don't use join_paths() (deprecated)

 tepl/meson.build | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
---
diff --git a/tepl/meson.build b/tepl/meson.build
index d581049..4f11758 100644
--- a/tepl/meson.build
+++ b/tepl/meson.build
@@ -113,7 +113,7 @@ TEPL_STATIC_DEP = declare_dependency(
   dependencies: TEPL_DEPS
 )
 
-symbol_map = join_paths(meson.current_source_dir(), 'symbol.map')
+symbol_map = meson.current_source_dir() / 'symbol.map'
 
 tepl_shared_lib = shared_library(
   'tepl-@0@'.format(TEPL_API_VERSION),