[lldb][AArch64] Enable int128 test

Other 128 bit tests run on AArch64 fine, it's
Arm (as in 32 bit Arm) that needs to be skipped.

lldb/test/API/functionalities/data-formatter/builtin-formats/TestBuiltinFormats.py

@@ -22,7 +22,7 @@ class TestCase(TestBase):
     @no_debug_info_test
     @skipIfWindows
     # uint128_t not available on arm.
-    @skipIf(archs=['arm', 'aarch64'])
+    @skipIf(archs=['arm'])
     def test(self):
         self.build()
         lldbutil.run_to_source_breakpoint(self, "// break here", lldb.SBFileSpec("main.cpp"))