WII: Fix correct keycode for virtual keyboard trigger.

As the virtual keyboard trigger has been moved to CTRL-F7, the previous
code which generates a unmodified F7 event to do this will not work.

However, due to the complexity of this code, directly calling the
virtual keyboard trigger event could have side effects, so have instead
just added the CTRL modifier to fix this.

This should be fixed if possible to use EVENT_VIRTUAL_KEYBOARD.
ANDROID: Fix correct keycode in keymapper for virtual keyboard trigger.

As the virtual keyboard trigger has been moved to CTRL-F7, the previous
code which generates a unmodified F7 event to do this will not work.

However, due to the complexity of this code, directly calling the
virtual keyboard trigger event could have side effects, so have instead
just added the CTRL modifier to fix this.

This should be fixed if possible to use EVENT_VIRTUAL_KEYBOARD.
CONFIGURE: Enable virtual keyboard support for Win32 builds.