[OpenMP][lit] Disable flaky test tasking/issue-94260-2.c (#176452)

The test sporadically fails on Linux. See
llvm/llvm-project#176451 for more info.

Signed-off-by: Nick Sarnie <nick.sarnie@intel.com>

Author: sarnex

openmp/runtime/test/tasking/issue-94260-2.c

@@ -1,5 +1,8 @@
 // RUN: %libomp-compile-and-run
 
+// https://github.com/llvm/llvm-project/issues/176451
+// UNSUPPORTED: linux && x86-target-arch
+
 #include <stdio.h>
 #include <omp.h>