Switch header convention from #include "SDL.h" to #include <SDL3/SDLh>

I ran this script in the include directory:
```sh
sed -i '' -e 's,#include "\(SDL.*\)",#include <SDL3/\1>,' *.h
```

I ran this script in the src directory:
```sh
for i in ../include/SDL3/SDL*.h
do hdr=$(basename $i)
   if [ x"$(echo $hdr | egrep 'SDL_main|SDL_name|SDL_test|SDL_syswm|SDL_opengl|SDL_egl|SDL_vulkan')" != x ]; then
        find . -type f -exec sed -i '' -e 's,#include "\('$hdr'\)",#include <SDL3/\1>,' {} \;
    else
        find . -type f -exec sed -i '' -e '/#include "'$hdr'"/d' {} \;
    fi
done
```

Fixes https://github.com/libsdl-org/SDL/issues/6575

src/sensor/SDL_sensor.c

@@ -22,9 +22,6 @@
 
 /* This is the sensor API for Simple DirectMedia Layer */
 
-#include "SDL.h"
-#include "SDL_atomic.h"
-#include "SDL_events.h"
 #include "SDL_syssensor.h"
 
 #if !SDL_EVENTS_DISABLED

src/sensor/SDL_sensor_c.h

@@ -26,7 +26,6 @@
 struct _SDL_SensorDriver;
 
 /* Useful functions and variables from SDL_sensor.c */
-#include "SDL_sensor.h"
 
 /* Function to get the next available sensor instance ID */
 extern SDL_SensorID SDL_GetNextSensorInstanceID(void);

src/sensor/SDL_syssensor.h

@@ -25,7 +25,6 @@
 
 /* This is the system specific header for the SDL sensor API */
 
-#include "SDL_sensor.h"
 #include "SDL_sensor_c.h"
 
 /* The SDL sensor structure */

src/sensor/android/SDL_androidsensor.c

@@ -25,8 +25,6 @@
 /* This is the system specific header for the SDL sensor API */
 #include <android/sensor.h>
 
-#include "SDL_error.h"
-#include "SDL_sensor.h"
 #include "SDL_androidsensor.h"
 #include "../SDL_syssensor.h"
 #include "../SDL_sensor_c.h"

src/sensor/coremotion/SDL_coremotionsensor.m

@@ -25,8 +25,6 @@
 /* This is the system specific header for the SDL sensor API */
 #include <CoreMotion/CoreMotion.h>
 
-#include "SDL_error.h"
-#include "SDL_sensor.h"
 #include "SDL_coremotionsensor.h"
 #include "../SDL_syssensor.h"
 #include "../SDL_sensor_c.h"

src/sensor/dummy/SDL_dummysensor.c

@@ -22,8 +22,6 @@
 
 #if defined(SDL_SENSOR_DUMMY) || defined(SDL_SENSOR_DISABLED)
 
-#include "SDL_error.h"
-#include "SDL_sensor.h"
 #include "SDL_dummysensor.h"
 #include "../SDL_syssensor.h"
 

src/sensor/vita/SDL_vitasensor.c

@@ -22,8 +22,6 @@
 
 #if defined(SDL_SENSOR_VITA)
 
-#include "SDL_error.h"
-#include "SDL_sensor.h"
 #include "SDL_vitasensor.h"
 #include "../SDL_syssensor.h"
 #include <psp2/motion.h>

src/sensor/windows/SDL_windowssensor.c

@@ -22,9 +22,6 @@
 
 #if defined(SDL_SENSOR_WINDOWS)
 
-#include "SDL_error.h"
-#include "SDL_mutex.h"
-#include "SDL_sensor.h"
 #include "SDL_windowssensor.h"
 #include "../SDL_syssensor.h"
 #include "../../core/windows/SDL_windows.h"