Documentation: kernel-api: add bitmap operations from linux/bitmap.h

Add <linux/bitmap.h> to kernel-api Bitmap Operations section.
Fix kernel-doc nitpicks in <linux/bitmap.h>.

Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Acked-by: Yury Norov <ynorov@caviumnetworks.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
diff --git a/Documentation/core-api/kernel-api.rst b/Documentation/core-api/kernel-api.rst
index e557509..f37c73f 100644
--- a/Documentation/core-api/kernel-api.rst
+++ b/Documentation/core-api/kernel-api.rst
@@ -59,6 +59,9 @@
 .. kernel-doc:: lib/bitmap.c
    :internal:
 
+.. kernel-doc:: include/linux/bitmap.h
+   :internal:
+
 Command-line Parsing
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