gdb: make-target-delegates.py: make one string raw

Fixes the following flake8 warning:

  make-target-delegates.py:36:39: W605 invalid escape sequence '\s'

Change-Id: I25eeb296f55765e17e5217a2d1e49018f63a3acd
Reviewed-By: Tom Tromey <tom@tromey.com>
Reviewed-By: Andrew Burgess <aburgess@redhat.com>
diff --git a/gdb/make-target-delegates.py b/gdb/make-target-delegates.py
index 969f21b..2df84cd 100755
--- a/gdb/make-target-delegates.py
+++ b/gdb/make-target-delegates.py
@@ -33,7 +33,7 @@
 # Match a C symbol.
 SYMBOL = "[a-zA-Z_][a-zA-Z0-9_]*"
 # Match the name part of a method in struct target_ops.
-NAME_PART = r"(?P<name>" + SYMBOL + ")\s"
+NAME_PART = r"(?P<name>" + SYMBOL + r")\s"
 # Match the arguments to a method.
 ARGS_PART = r"(?P<args>\(.*\))"
 # We strip the indentation so here we only need the caret.