vo_gpu: semi-fix --gpu-context/--gpu-api options and help output

This was confusing at best. Change it to output the actual choices.
(Seems like in the end it's always me who has to clean up other people's
bullshit.)

Context names were not unique - but they should be, so fix it. The whole
point of the original --opengl-backend option was to side-step the
tricky auto-detection, so you know exactly what you get. The goal of
this commit is to make --gpu-context work the same way. Fix the
non-unique names by appending "vk" to the names.

Keep in mind that this was not suitable for slecting the "UI" backend
anyway, since "x11" would force GLX, whereas people on not-NVIDIA
actually want "x11egl". Users trying to use --gpu-context=x11 to force
the X11 backend would always end up with GLX, which would at least break
VAAPI hardware decoding for them. Basically the idea that this option
could select the "UI" type is completely broken - it selects an
implementation, which implies a UI. Selecting the UI type This would
require a separate mechanism. (Although in theory this separate
mechanism could be part of the --gpu-context option - in any case,
someone would have to implement it.)

To achieve help output that can actually be understood, just duplicate
the code. Most of that code is duplicated anyway, and trying to share
just the list code with the result of making the output unreadable
doesn't make too much sense. If we wanted to save code/effort, we could
just remove the help output altogether.

--gpu-api has non-unique entries, and it would be nice to group them
(e.g. list all OpenGL capable contexts with "opengl"), but C makes this
simple idea too much of a pain, so don't do it.

Also remove a stray tab from the android entry on the manpage.

1 files changed, 1 insertions, 1 deletions

diff --git a/video/out/vulkan/context_wayland.c b/video/out/vulkan/context_wayland.c
index 92ee7aa1a9..7276775242 100644
--- a/video/out/vulkan/context_wayland.c
+++ b/video/out/vulkan/context_wayland.c
@@ -123,7 +123,7 @@ static void wayland_vk_wait_events(struct ra_ctx *ctx, int64_t until_time_us)
 
 const struct ra_ctx_fns ra_ctx_vulkan_wayland = {
     .type           = "vulkan",
-    .name           = "wayland",
+    .name           = "waylandvk",
     .reconfig       = wayland_vk_reconfig,
     .control        = wayland_vk_control,
     .wakeup         = wayland_vk_wakeup,