docs/misra: exclude gdbsx from MISRA compliance

These files are used when debugging Xen, and are not meant to comply
with MISRA rules at the moment.

No functional change.

Signed-off-by: Nicola Vetrini <nicola.vetrini@bugseng.com>
Acked-by: Jan Beulich <jbeulich@suse.com>

docs/misra/exclude-list.json

@@ -77,6 +77,14 @@
             "rel_path": "arch/x86/dmi_scan.c",
             "comment": "Imported from Linux, ignore for now"
         },
+        {
+            "rel_path": "arch/x86/gdbsx.c",
+            "comment": "Used for debugging Xen, ignore for now"
+        },
+        {
+            "rel_path": "arch/x86/include/asm/gdbsx.h",
+            "comment": "Used for debugging Xen, ignore for now"
+        },
         {
             "rel_path": "arch/x86/mpparse.c",
             "comment": "Imported from Linux, ignore for now"