Arm backend: aot_arm_compiler.py support BundleIO output file without a path (#18871)

BundleIO output generation needed the specified output file name to be
supplied with a folder, so if you wanted to output a file in the current
folder you needed to add "./" in front of the file name like
"./file.bpte" this change fixes this problem, the normal .pte generation
already supported this.

Signed-off-by: Zingo Andersen <Zingo.Andersen@arm.com>

Author: zingo

backends/arm/scripts/aot_arm_compiler.py

@@ -778,7 +778,8 @@ def _save_bpte_program(
 
     # Generate BundledProgram
     output_dir = os.path.dirname(output_name)
-    os.makedirs(output_dir, exist_ok=True)
+    if output_dir:
+        os.makedirs(output_dir, exist_ok=True)
     _save_bundled_program(exec_prog, method_test_suites, output_name)