SDL API renaming: SDL_gamecontroller.h

SDL_gamecontroller.h has been renamed SDL_gamepad.h, and all APIs have been renamed to match.

Fixes https://github.com/libsdl-org/SDL/issues/6885

.gitignore

@@ -61,17 +61,17 @@ Release
 *.ncb
 *.suo
 *.sdf
-VisualC/tests/controllermap/axis.bmp
-VisualC/tests/controllermap/button.bmp
-VisualC/tests/controllermap/controllermap.bmp
-VisualC/tests/controllermap/controllermap_back.bmp
+VisualC/tests/gamepadmap/axis.bmp
+VisualC/tests/gamepadmap/button.bmp
+VisualC/tests/gamepadmap/gamepadmap.bmp
+VisualC/tests/gamepadmap/gamepadmap_back.bmp
 VisualC/tests/loopwave/sample.wav
 VisualC/tests/testautomation/CompareSurfaces0001_Reference.bmp
 VisualC/tests/testautomation/CompareSurfaces0001_TestOutput.bmp
-VisualC/tests/testgamecontroller/axis.bmp
-VisualC/tests/testgamecontroller/button.bmp
-VisualC/tests/testgamecontroller/controllermap.bmp
-VisualC/tests/testgamecontroller/controllermap_back.bmp
+VisualC/tests/testgamepad/axis.bmp
+VisualC/tests/testgamepad/button.bmp
+VisualC/tests/testgamepad/gamepadmap.bmp
+VisualC/tests/testgamepad/gamepadmap_back.bmp
 VisualC/tests/testoverlay2/moose.dat
 VisualC/tests/testrendertarget/icon.bmp
 VisualC/tests/testrendertarget/sample.bmp
@@ -87,7 +87,7 @@ android-project/.gradle/
 
 test/checkkeys
 test/checkkeysthreads
-test/controllermap
+test/gamepadmap
 test/loopwave
 test/loopwavequeue
 test/testatomic
@@ -105,7 +105,7 @@ test/testerror
 test/testevdev
 test/testfile
 test/testfilesystem
-test/testgamecontroller
+test/testgamepad
 test/testgeometry
 test/testgesture
 test/testgl2