Update docs and tests for ARM gdb support

Updated docs to now show arm is supported.
Updated the build test to run on aarch

Signed-off-by: Jack Thomson <jackabt@amazon.com>

Author: JackThomson2

docs/gdb-debugging.md

@@ -2,7 +2,7 @@
 
 Firecracker supports debugging the guest kernel via GDB remote serial protocol.
 This allows us to connect GDB to the firecracker process and step through debug
-the guest kernel. Currently only debugging on x86 is supported.
+the guest kernel.
 
 The GDB feature requires Firecracker to be booted with a config file.
 
@@ -108,3 +108,7 @@ command in the GDB session which will terminate both.
 
 - Currently we support a limited subset of cpu registers for get and set
   operations, if more are required feel free to contribute.
+
+- Some assumptions around virtual address configuration on arm have been made.
+  If the current translation implementation doesn't cover a specific setup, feel
+  free to contribute.

tests/integration_tests/build/test_gdb.py

@@ -4,15 +4,12 @@
 
 import platform
 
-import pytest
-
 import host_tools.cargo_build as host
 
 MACHINE = platform.machine()
 TARGET = "{}-unknown-linux-musl".format(MACHINE)
 
 
-@pytest.mark.skipif(MACHINE != "x86_64", reason="GDB runs only on x86_64.")
 def test_gdb_compiles():
     """Checks that Firecracker compiles with GDB enabled"""