[LLDB] Mark some xfails for arm-linux

This patch marks following tests as xfail for arm-linux target.

lldb/test/API/functionalities/load_using_paths/TestLoadUsingPaths.py
lldb/test/API/python_api/thread/TestThreadAPI.py
lldb/test/Shell/Recognizer/assert.test

Bugs have been filed for all of them for the corresponding failing
component.

lldb/test/API/functionalities/load_using_paths/TestLoadUsingPaths.py

@@ -40,6 +40,7 @@ class LoadUsingPathsTestCase(TestBase):
     @not_remote_testsuite_ready
     @skipIfWindows  # Windows doesn't have dlopen and friends, dynamic libraries work differently
     @expectedFlakeyNetBSD
+    @expectedFailureAll(oslist=["linux"], archs=['arm'], bugnumber="llvm.org/pr45894")
     def test_load_using_paths(self):
         """Test that we can load a module by providing a set of search paths."""
         if self.platformIsDarwin():

lldb/test/API/python_api/thread/TestThreadAPI.py

@@ -38,6 +38,7 @@ class ThreadAPITestCase(TestBase):
         self.run_to_address(self.exe_name)
 
     @add_test_categories(['pyapi'])
+    @expectedFailureAll(oslist=["linux"], archs=['arm'], bugnumber="llvm.org/pr45892")
     @expectedFailureAll(oslist=['freebsd'], bugnumber='llvm.org/pr20476')
     @expectedFailureAll(oslist=["windows"])
     @expectedFailureNetBSD

lldb/test/Shell/Recognizer/assert.test

@@ -1,3 +1,4 @@
+// XFAIL: target-arm && linux-gnu
 # UNSUPPORTED: system-windows
 # RUN: %clang_host -g -O0 %S/Inputs/assert.c -o %t.out
 # RUN: %lldb -b -s %s %t.out | FileCheck %s