[media] docs-rst: Convert MC uAPI to use C function references

Name all ioctl references and make them match the ioctls that
are documented. That will improve the cross-reference index,
as it will have all ioctls and syscalls there.

While here, improve the documentation to make them to look more
like the rest of the document.

Signed-off-by: Mauro Carvalho Chehab <[e-mail]>

Documentation/media/uapi/mediactl/media-func-close.rst

···
 
 
 .. c:function:: int close( int fd )
-
+    :name: mc-close
 
 Arguments
 =========
 
 ``fd``
-    File descriptor returned by :ref:`open() <func-open>`.
+    File descriptor returned by :c:func:`open() <mc-open>`.
 
 
 Description

Documentation/media/uapi/mediactl/media-func-ioctl.rst

···
 
 
 .. c:function:: int ioctl( int fd, int request, void *argp )
-
+    :name: mc-ioctl
 
 Arguments
 =========
 
 ``fd``
-    File descriptor returned by :ref:`open() <func-open>`.
+    File descriptor returned by :c:func:`open() <mc-open>`.
 
 ``request``
     Media ioctl request code as defined in the media.h header file, for

Documentation/media/uapi/mediactl/media-func-open.rst

···
 
 
 .. c:function:: int open( const char *device_name, int flags )
-
+    :name: mc-open
 
 Arguments
 =========

Documentation/media/uapi/mediactl/media-ioc-device-info.rst

···
 Synopsis
 ========
 
-.. c:function:: int ioctl( int fd, int request, struct media_device_info *argp )
+.. c:function:: int ioctl( int fd, MEDIA_IOC_DEVICE_INFO, struct media_device_info *argp )
+    :name: MEDIA_IOC_DEVICE_INFO
 
 
 Arguments
···
 
 ``fd``
     File descriptor returned by :ref:`open() <media-func-open>`.
-
-``request``
-    MEDIA_IOC_DEVICE_INFO
 
 ``argp``
 

Documentation/media/uapi/mediactl/media-ioc-enum-entities.rst

···
 Synopsis
 ========
 
-.. c:function:: int ioctl( int fd, int request, struct media_entity_desc *argp )
+.. c:function:: int ioctl( int fd, MEDIA_IOC_ENUM_ENTITIES, struct media_entity_desc *argp )
+    :name: MEDIA_IOC_ENUM_ENTITIES
 
 
 Arguments
···
 
 ``fd``
     File descriptor returned by :ref:`open() <media-func-open>`.
-
-``request``
-    MEDIA_IOC_ENUM_ENTITIES
 
 ``argp``
 

Documentation/media/uapi/mediactl/media-ioc-enum-links.rst

···
 Synopsis
 ========
 
-.. c:function:: int ioctl( int fd, int request, struct media_links_enum *argp )
+.. c:function:: int ioctl( int fd, MEDIA_IOC_ENUM_LINKS, struct media_links_enum *argp )
+    :name: MEDIA_IOC_ENUM_LINKS
 
 
 Arguments
···
 
 ``fd``
     File descriptor returned by :ref:`open() <media-func-open>`.
-
-``request``
-    MEDIA_IOC_ENUM_LINKS
 
 ``argp``
 

Documentation/media/uapi/mediactl/media-ioc-g-topology.rst

···
 Synopsis
 ========
 
-.. c:function:: int ioctl( int fd, int request, struct media_v2_topology *argp )
+.. c:function:: int ioctl( int fd, MEDIA_IOC_G_TOPOLOGY, struct media_v2_topology *argp )
+    :name: MEDIA_IOC_G_TOPOLOGY
 
 
 Arguments
···
 
 ``fd``
     File descriptor returned by :ref:`open() <media-func-open>`.
-
-``request``
-    MEDIA_IOC_G_TOPOLOGY
 
 ``argp``
 

Documentation/media/uapi/mediactl/media-ioc-setup-link.rst

···
 Synopsis
 ========
 
-.. c:function:: int ioctl( int fd, int request, struct media_link_desc *argp )
+.. c:function:: int ioctl( int fd, MEDIA_IOC_SETUP_LINK, struct media_link_desc *argp )
+    :name: MEDIA_IOC_SETUP_LINK
 
 
 Arguments
···
 
 ``fd``
     File descriptor returned by :ref:`open() <media-func-open>`.
-
-``request``
-    MEDIA_IOC_SETUP_LINK
 
 ``argp``