[media] dvb uapi docs: enums are passed by value, not reference

Since 2015, the documentation for FE_DISEQC_SEND_BURST, FE_SET_TONE
and FE_SET_VOLTAGE are incorrectly saying that the enums are passed
by reference. They aren't: they're passed by value.

Fix the documentation to reflect reality.

Fixes: 81959d99 ("[media] DocBook: better document FE_DISEQC_SEND_BURST ioctl")
Fixes: d6b6d346 ("[media] DocBook: better document FE_SET_VOLTAGE ioctl")
Fixes: 6dc59e7a ("[media] DocBook: better document FE_SET_TONE ioctl")
Reported-by: Thierry Lelegard <thierry.lelegard@free.fr>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>

Documentation/media/uapi/dvb/fe-diseqc-send-burst.rst

@@ -15,7 +15,7 @@ FE_DISEQC_SEND_BURST - Sends a 22KHz tone burst for 2x1 mini DiSEqC satellite se
 Synopsis
 ========
 
-.. c:function:: int ioctl( int fd, FE_DISEQC_SEND_BURST, enum fe_sec_mini_cmd *tone )
+.. c:function:: int ioctl( int fd, FE_DISEQC_SEND_BURST, enum fe_sec_mini_cmd tone )
     :name: FE_DISEQC_SEND_BURST
 
 
@@ -26,7 +26,7 @@ Arguments
     File descriptor returned by :ref:`open() <frontend_f_open>`.
 
 ``tone``
-    pointer to enum :c:type:`fe_sec_mini_cmd`
+    an integer enumered value described at :c:type:`fe_sec_mini_cmd`
 
 
 Description

Documentation/media/uapi/dvb/fe-set-tone.rst

@@ -15,7 +15,7 @@ FE_SET_TONE - Sets/resets the generation of the continuous 22kHz tone.
 Synopsis
 ========
 
-.. c:function:: int ioctl( int fd, FE_SET_TONE, enum fe_sec_tone_mode *tone )
+.. c:function:: int ioctl( int fd, FE_SET_TONE, enum fe_sec_tone_mode tone )
     :name: FE_SET_TONE
 
 
@@ -26,7 +26,7 @@ Arguments
     File descriptor returned by :ref:`open() <frontend_f_open>`.
 
 ``tone``
-    pointer to enum :c:type:`fe_sec_tone_mode`
+    an integer enumered value described at :c:type:`fe_sec_tone_mode`
 
 
 Description

Documentation/media/uapi/dvb/fe-set-voltage.rst

@@ -15,7 +15,7 @@ FE_SET_VOLTAGE - Allow setting the DC level sent to the antenna subsystem.
 Synopsis
 ========
 
-.. c:function:: int ioctl( int fd, FE_SET_VOLTAGE, enum fe_sec_voltage *voltage )
+.. c:function:: int ioctl( int fd, FE_SET_VOLTAGE, enum fe_sec_voltage voltage )
     :name: FE_SET_VOLTAGE
 
 
@@ -26,10 +26,7 @@ Arguments
     File descriptor returned by :ref:`open() <frontend_f_open>`.
 
 ``voltage``
-    pointer to enum :c:type:`fe_sec_voltage`
-
-    Valid values are described at enum
-    :c:type:`fe_sec_voltage`.
+    an integer enumered value described at :c:type:`fe_sec_voltage`
 
 
 Description