Update for SDL3 coding style (#6717)

I updated .clang-format and ran clang-format 14 over the src and test directories to standardize the code base.

In general I let clang-format have it's way, and added markup to prevent formatting of code that would break or be completely unreadable if formatted.

The script I ran for the src directory is added as build-scripts/clang-format-src.sh

This fixes:
#6592
#6593
#6594

(cherry picked from commit 5750bcb174)

src/filesystem/android/SDL_sysfilesystem.c

@@ -45,7 +45,7 @@ SDL_GetPrefPath(const char *org, const char *app)
 {
     const char *path = SDL_AndroidGetInternalStoragePath();
     if (path) {
-        size_t pathlen = SDL_strlen(path)+2;
+        size_t pathlen = SDL_strlen(path) + 2;
         char *fullpath = (char *)SDL_malloc(pathlen);
         if (fullpath == NULL) {
             SDL_OutOfMemory();