SDL: Fix wrong value for thread priorities following official PSP Docs

SDL Commits
1 
From 8ed0cc430075d2c9ddc7be14c402caf43bd6c6bb Mon Sep 17 00:00:00 2001
From: Francisco Javier Trujillo Mata <[EMAIL REDACTED]>
Date: Wed, 15 Dec 2021 22:30:04 +0100
Subject: [PATCH] Fix wrong value for thread priorities following official PSP
 Docs

---
 src/thread/psp/SDL_systhread.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/src/thread/psp/SDL_systhread.c b/src/thread/psp/SDL_systhread.c
index 39ce21e38cc..e2a3448c967 100644
--- a/src/thread/psp/SDL_systhread.c
+++ b/src/thread/psp/SDL_systhread.c
@@ -95,13 +95,13 @@ int SDL_SYS_SetThreadPriority(SDL_ThreadPriority priority)
     int value;
 
     if (priority == SDL_THREAD_PRIORITY_LOW) {
-        value = 19;
+        value = 111;
     } else if (priority == SDL_THREAD_PRIORITY_HIGH) {
-        value = -10;
+        value = 32;
     } else if (priority == SDL_THREAD_PRIORITY_TIME_CRITICAL) {
-        value = -20;
+        value = 16;
     } else {
-        value = 0;
+        value = 50;
     }
 
     return sceKernelChangeThreadPriority(sceKernelGetThreadId(),value);