doc-rst: mediactl: fix some wrong cross references

Those cross references should point to media control syscalls,
and not to V4L ones.
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>

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

@@ -40,7 +40,7 @@ are freed. The device configuration remain unchanged.
 Return Value
 ============
 
-:ref:`close() <func-close>` returns 0 on success. On error, -1 is returned, and
+:ref:`close() <media-func-close>` returns 0 on success. On error, -1 is returned, and
 ``errno`` is set appropriately. Possible error codes are:
 
 EBADF

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

@@ -40,8 +40,8 @@ Arguments
 Description
 ===========
 
-The :ref:`ioctl() <func-ioctl>` function manipulates media device parameters.
-The argument ``fd`` must be an open file descriptor.
+The :ref:`ioctl() <media-func-ioctl>` function manipulates media device
+parameters. The argument ``fd`` must be an open file descriptor.
 
 The ioctl ``request`` code specifies the media function to be called. It
 has encoded in it whether the argument is an input, output or read/write

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

@@ -37,7 +37,7 @@ Arguments
 Description
 ===========
 
-To open a media device applications call :ref:`open() <func-open>` with the
+To open a media device applications call :ref:`open() <media-func-open>` with the
 desired device name. The function has no side effects; the device
 configuration remain unchanged.