qapi: Plug trivial documentation holes around former simple unions

The conversion of simple to flat unions left the @data members
undocumented.  Add documentation where it's trivial.  Copy verbatim
from the wrapped type's description where possible.

Leftovers: String (to be taken care of in the next commit), and
TransActionAction (left for another day).

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-ID: <20240205074709.3613229-13-armbru@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>

qapi/ui.json

@@ -990,6 +990,8 @@
 ##
 # @IntWrapper:
 #
+# @data: a numeric key code
+#
 # Since: 1.3
 ##
 { 'struct': 'IntWrapper',
@@ -998,6 +1000,8 @@
 ##
 # @QKeyCodeWrapper:
 #
+# @data: An enumeration of key name
+#
 # Since: 1.3
 ##
 { 'struct': 'QKeyCodeWrapper',
@@ -1175,6 +1179,8 @@
 ##
 # @InputKeyEventWrapper:
 #
+# @data: Keyboard input event
+#
 # Since: 2.0
 ##
 { 'struct': 'InputKeyEventWrapper',
@@ -1183,6 +1189,8 @@
 ##
 # @InputBtnEventWrapper:
 #
+# @data: Pointer button input event
+#
 # Since: 2.0
 ##
 { 'struct': 'InputBtnEventWrapper',
@@ -1191,6 +1199,8 @@
 ##
 # @InputMoveEventWrapper:
 #
+# @data: Pointer motion input event
+#
 # Since: 2.0
 ##
 { 'struct': 'InputMoveEventWrapper',
@@ -1199,6 +1209,8 @@
 ##
 # @InputMultiTouchEventWrapper:
 #
+# @data: MultiTouch input event
+#
 # Since: 8.1
 ##
 { 'struct': 'InputMultiTouchEventWrapper',