[lldb] Fix a few lldb-server tests on Apple Silicon

This fixes TestGdbRemoteSingleStep.py and TestGdbRemote_vCont.py. This
patch updates the test to account for the possibility that the constants
are already materialized. This appears to behave differently between
embedded arm64 devices and Apple Silicon.

Author: JDevlieghere

lldb/packages/Python/lldbsuite/test/tools/lldb-server/gdbremote_testcase.py

@@ -1537,17 +1537,18 @@ def single_step_only_steps_one_instruction(
         # variable value
         if re.match("s390x", arch):
             expected_step_count = 2
-        # ARM64 requires "4" instructions: 2 to compute the address (adrp, add),
-        # one to materialize the constant (mov) and the store
+        # ARM64 requires "4" instructions: 2 to compute the address (adrp,
+        # add), one to materialize the constant (mov) and the store. Once
+        # addresses and constants are materialized, only one instruction is
+        # needed.
         if re.match("arm64", arch):
-            expected_step_count = 4
-
-        self.assertEqual(step_count, expected_step_count)
-
-        # ARM64: Once addresses and constants are materialized, only one
-        # instruction is needed.
-        if re.match("arm64", arch):
-            expected_step_count = 1
+            before_materialization_step_count = 4
+            after_matrialization_step_count = 1
+            self.assertIn(step_count, [before_materialization_step_count,
+                                       after_matrialization_step_count])
+            expected_step_count = after_matrialization_step_count
+        else:
+            self.assertEqual(step_count, expected_step_count)
 
         # Verify we hit the next state.
         args["expected_g_c1"] = "0"