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

src/loadso/dummy/SDL_sysloadso.c

@@ -25,7 +25,6 @@
 /* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
 /* System dependent library loading routines                           */
 
-
 void *
 SDL_LoadObject(const char *sofile)
 {
@@ -42,8 +41,7 @@ SDL_LoadFunction(void *handle, const char *name)
     return NULL;
 }
 
-void
-SDL_UnloadObject(void *handle)
+void SDL_UnloadObject(void *handle)
 {
     /* no-op. */
 }