kernel-doc: Fix parsing of DECLARE_BITMAP in struct

Some documented structures in the kernel use DECLARE_BITMAP to create
arrays of unsigned longs to store information using the bitmap functions.
These have to be replaced with a parsable version for kernel-doc.

For example a simple input like

    /**
     * struct something - some test
     * @members: active members
     */
    struct something {
    	DECLARE_BITMAP(members, MAX_MEMBERS);
    };

resulted in parsing warnings like

    warning: No description found for parameter 'MAX_MEMBERS)'
    warning: Excess struct/union/enum/typedef member 'members' description in 'something'

Signed-off-by: Conchúr Navid <conchur@web.de>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
diff --git a/scripts/kernel-doc b/scripts/kernel-doc
index f5c2971..9015b18 100755
--- a/scripts/kernel-doc
+++ b/scripts/kernel-doc
@@ -1816,6 +1816,8 @@
 	$members =~ s/__attribute__\s*\(\([a-z,_\*\s\(\)]*\)\)//i;
 	$members =~ s/__aligned\s*\([^;]*\)//gos;
 	$members =~ s/\s*CRYPTO_MINALIGN_ATTR//gos;
+	# replace DECLARE_BITMAP
+	$members =~ s/DECLARE_BITMAP\s*\(([^,)]+), ([^,)]+)\)/unsigned long $1\[BITS_TO_LONGS($2)\]/gos;
 
 	create_parameterlist($members, ';', $file);
 	check_sections($file, $declaration_name, "struct", $sectcheck, $struct_actual, $nested);