docs: sphinx: kerneldoc: ignore "\" characters from options

Documentation/driver-api/infiniband.rst has a kernel-doc tag
with "\" characters at the end:

	.. kernel-doc:: drivers/infiniband/ulp/iser/iscsi_iser.c
	   :functions: iscsi_iser_pdu_alloc iser_initialize_task_headers \
	        iscsi_iser_task_init iscsi_iser_mtask_xmit iscsi_iser_task_xmit \
	        iscsi_iser_cleanup_task iscsi_iser_check_protection \
	        iscsi_iser_conn_create iscsi_iser_conn_bind \
	        iscsi_iser_conn_start iscsi_iser_conn_stop \
	        iscsi_iser_session_destroy iscsi_iser_session_create \
	        iscsi_iser_set_param iscsi_iser_ep_connect iscsi_iser_ep_poll \
	        iscsi_iser_ep_disconnect

This is not handled well, as the "\" strings will be just stored inside
Sphinx options.

While the actual problem deserves being fixed, better to relax the
keneldoc.py extension to silently strip "\" from the end of strings,
as otherwise this may cause troubles when preparing arguments to
be executed by kernel-doc.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Link: https://lore.kernel.org/r/4c652d6c57b20500c135b95294e554d9e9a97f42.1744106242.git.mchehab+huawei@kernel.org

Author: mchehab

Documentation/sphinx/kerneldoc.py

@@ -118,6 +118,10 @@ def run(self):
             identifiers = self.options.get('identifiers').split()
             if identifiers:
                 for i in identifiers:
+                    i = i.rstrip("\\").strip()
+                    if not i:
+                        continue
+
                     cmd += ['-function', i]
             else:
                 cmd += ['-no-doc-sections']
@@ -126,9 +130,17 @@ def run(self):
             no_identifiers = self.options.get('no-identifiers').split()
             if no_identifiers:
                 for i in no_identifiers:
+                    i = i.rstrip("\\").strip()
+                    if not i:
+                        continue
+
                     cmd += ['-nosymbol', i]
 
         for pattern in export_file_patterns:
+            pattern = pattern.rstrip("\\").strip()
+            if not pattern:
+                continue
+
             for f in glob.glob(env.config.kerneldoc_srctree + '/' + pattern):
                 env.note_dependency(os.path.abspath(f))
                 cmd += ['-export-file', f]