media: docs: make DVB documents more compatible with Sphinx 3.1+

Sphinx 3.x broke support for the cdomain.py extension, as the
c domain code was rewritten. Due to that, the c tags need to
be re-written, in order to use the new c domain notation.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>

Documentation/userspace-api/media/dvb/fe-read-status.rst

@@ -1,4 +1,5 @@
 .. SPDX-License-Identifier: GFDL-1.1-no-invariants-or-later
+.. c:namespace:: DTV.fe
 
 .. _FE_READ_STATUS:
 
@@ -11,25 +12,23 @@ Name
 
 FE_READ_STATUS - Returns status information about the front-end. This call only requires - read-only access to the device
 
-
 Synopsis
 ========
 
-.. c:function:: int ioctl( int fd, FE_READ_STATUS, unsigned int *status )
-    :name: FE_READ_STATUS
+.. c:macro:: FE_READ_STATUS
 
+``int ioctl(int fd, FE_READ_STATUS, unsigned int *status)``
 
 Arguments
 =========
 
 ``fd``
-    File descriptor returned by :ref:`open() <frontend_f_open>`.
+    File descriptor returned by :c:func:`open()`.
 
 ``status``
     pointer to a bitmask integer filled with the values defined by enum
     :c:type:`fe_status`.
 
-
 Description
 ===========
 
@@ -44,7 +43,6 @@ written.
    varies according with the architecture. This needs to be fixed in the
    future.
 
-
 int fe_status
 =============
 
@@ -52,7 +50,6 @@ The fe_status parameter is used to indicate the current state and/or
 state changes of the frontend hardware. It is produced using the enum
 :c:type:`fe_status` values on a bitmask
 
-
 Return Value
 ============