Valgrind: Restore a suppression that got accidentally removed.

tools/valgrind/memcheck/suppressions.txt

Index: tools/valgrind/memcheck/suppressions.txt
diff --git a/tools/valgrind/memcheck/suppressions.txt b/tools/valgrind/memcheck/suppressions.txt
index 53adf44afb95cb051b3906a1cf0bc206b2faaa54..0e213c1503589f2579c703ef4d6f04bfca5f61c2 100644
--- a/tools/valgrind/memcheck/suppressions.txt
+++ b/tools/valgrind/memcheck/suppressions.txt
@@ -1368,6 +1368,29 @@
    fun:_ZN8appcache17AppCacheDiskCache10ActiveCall17OnAsyncCompletionEi
 }
 {
+   bug_112278
+   Memcheck:Uninitialized
+   fun:fetch_texel_2d_f_rgba8888
+   ...
+   fun:sample_nearest_2d
+   fun:fetch_texel_lod
+   fun:fetch_texel
+   fun:_mesa_execute_program
+   fun:run_program*
+   fun:_swrast_exec_fragment_program
+   fun:shade_texture_span
+   fun:_swrast_write_rgba_span
+   fun:general_triangle
+   ...
+   fun:_swrast_Triangle
+   fun:triangle_rgba
+   ...
+   fun:run_render
+   fun:_tnl_run_pipeline
+   fun:_tnl_draw_prims
+   fun:_tnl_vbo_draw_prims
+}
+{
    bug_122457
    Memcheck:Leak
    fun:malloc