SDL: pulseaudio: Fix some function signatures that expect const pointers.

From 9504bb121d3951240d5c3a5980f45c9d71497317 Mon Sep 17 00:00:00 2001
From: "Ryan C. Gordon" <[EMAIL REDACTED]>
Date: Mon, 23 Aug 2021 00:47:25 -0400
Subject: [PATCH] pulseaudio: Fix some function signatures that expect const
 pointers.

This might have changed at some point in the Pulse API, or this might have
always been wrong, but we didn't notice because the dynamic loading code
hides it by casting things to void *. The static path, where it
assigns the function pointer directly, puts out a clear compiler warning,
though.
---
 src/audio/pulseaudio/SDL_pulseaudio.c | 12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/src/audio/pulseaudio/SDL_pulseaudio.c b/src/audio/pulseaudio/SDL_pulseaudio.c
index c97f15681c..d1997aad73 100644
--- a/src/audio/pulseaudio/SDL_pulseaudio.c
+++ b/src/audio/pulseaudio/SDL_pulseaudio.c
@@ -80,7 +80,7 @@ static void (*PULSEAUDIO_pa_mainloop_quit) (pa_mainloop *, int);
 static void (*PULSEAUDIO_pa_mainloop_free) (pa_mainloop *);
 
 static pa_operation_state_t (*PULSEAUDIO_pa_operation_get_state) (
-    pa_operation *);
+    const pa_operation *);
 static void (*PULSEAUDIO_pa_operation_cancel) (pa_operation *);
 static void (*PULSEAUDIO_pa_operation_unref) (pa_operation *);
 
@@ -92,7 +92,7 @@ static pa_operation * (*PULSEAUDIO_pa_context_get_sink_info_list) (pa_context *,
 static pa_operation * (*PULSEAUDIO_pa_context_get_source_info_list) (pa_context *, pa_source_info_cb_t, void *);
 static pa_operation * (*PULSEAUDIO_pa_context_get_sink_info_by_index) (pa_context *, uint32_t, pa_sink_info_cb_t, void *);
 static pa_operation * (*PULSEAUDIO_pa_context_get_source_info_by_index) (pa_context *, uint32_t, pa_source_info_cb_t, void *);
-static pa_context_state_t (*PULSEAUDIO_pa_context_get_state) (pa_context *);
+static pa_context_state_t (*PULSEAUDIO_pa_context_get_state) (const pa_context *);
 static pa_operation * (*PULSEAUDIO_pa_context_subscribe) (pa_context *, pa_subscription_mask_t, pa_context_success_cb_t, void *);
 static void (*PULSEAUDIO_pa_context_set_subscribe_callback) (pa_context *, pa_context_subscribe_cb_t, void *);
 static void (*PULSEAUDIO_pa_context_disconnect) (pa_context *);
@@ -101,12 +101,12 @@ static void (*PULSEAUDIO_pa_context_unref) (pa_context *);
 static pa_stream * (*PULSEAUDIO_pa_stream_new) (pa_context *, const char *,
     const pa_sample_spec *, const pa_channel_map *);
 static int (*PULSEAUDIO_pa_stream_connect_playback) (pa_stream *, const char *,
-    const pa_buffer_attr *, pa_stream_flags_t, pa_cvolume *, pa_stream *);
+    const pa_buffer_attr *, pa_stream_flags_t, const pa_cvolume *, pa_stream *);
 static int (*PULSEAUDIO_pa_stream_connect_record) (pa_stream *, const char *,
     const pa_buffer_attr *, pa_stream_flags_t);
-static pa_stream_state_t (*PULSEAUDIO_pa_stream_get_state) (pa_stream *);
-static size_t (*PULSEAUDIO_pa_stream_writable_size) (pa_stream *);
-static size_t (*PULSEAUDIO_pa_stream_readable_size) (pa_stream *);
+static pa_stream_state_t (*PULSEAUDIO_pa_stream_get_state) (const pa_stream *);
+static size_t (*PULSEAUDIO_pa_stream_writable_size) (const pa_stream *);
+static size_t (*PULSEAUDIO_pa_stream_readable_size) (const pa_stream *);
 static int (*PULSEAUDIO_pa_stream_begin_write) (pa_stream *, void **, size_t*);
 static int (*PULSEAUDIO_pa_stream_cancel_write) (pa_stream *);
 static int (*PULSEAUDIO_pa_stream_write) (pa_stream *, const void *, size_t,