crypto: doc - optimize compilation

The :functions: definition allows the specification of multiple
function references which prevents parsing the header file multiple
times.

Reported-by: Jani Nikula <jani.nikula@linux.intel.com>
Signed-off-by: Stephan Mueller <smueller@chronox.de>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
diff --git a/Documentation/crypto/api-rng.rst b/Documentation/crypto/api-rng.rst
index 0d7ee78..10ba743 100644
--- a/Documentation/crypto/api-rng.rst
+++ b/Documentation/crypto/api-rng.rst
@@ -11,22 +11,4 @@
    :doc: Random number generator API
 
 .. kernel-doc:: include/crypto/rng.h
-   :functions: crypto_alloc_rng
-
-.. kernel-doc:: include/crypto/rng.h
-   :functions: crypto_rng_alg
-
-.. kernel-doc:: include/crypto/rng.h
-   :functions: crypto_free_rng
-
-.. kernel-doc:: include/crypto/rng.h
-   :functions: crypto_rng_generate
-
-.. kernel-doc:: include/crypto/rng.h
-   :functions: crypto_rng_get_bytes
-
-.. kernel-doc:: include/crypto/rng.h
-   :functions: crypto_rng_reset
-
-.. kernel-doc:: include/crypto/rng.h
-   :functions: crypto_rng_seedsize
+   :functions: crypto_alloc_rng crypto_rng_alg crypto_free_rng crypto_rng_generate crypto_rng_get_bytes crypto_rng_reset crypto_rng_seedsize