Small SDL3 macOS fixes

[metayan]

gl_context is no longer a pointer
mouse x,y is float

Fixes these warnings when building macOS

+ ninja -C /src/scm/android/scrcpy/release/work/build-macos-x86_64
ninja: Entering directory `/src/scm/android/scrcpy/release/work/build-macos-x86_64'
[21/75] Compiling C object app/scrcpy.p/src_mouse_capture.c.o
../../../app/src/mouse_capture.c:89:33: warning: incompatible pointer types passing 'int *' to parameter of type 'float *' [-Wincompatible-pointer-types]
	SDL_GetGlobalMouseState(&mouse_x, &mouse_y);
				^~~~~~~~
/src/scm/android/scrcpy/app/deps/work/install/macos-native-static/include/SDL3/SDL_mouse.h:298:81: note: passing argument to parameter 'x' here
extern SDL_DECLSPEC SDL_MouseButtonFlags SDLCALL SDL_GetGlobalMouseState(float *x, float *y);
										^
../../../app/src/mouse_capture.c:89:43: warning: incompatible pointer types passing 'int *' to parameter of type 'float *' [-Wincompatible-pointer-types]
	SDL_GetGlobalMouseState(&mouse_x, &mouse_y);
					  ^~~~~~~~
/src/scm/android/scrcpy/app/deps/work/install/macos-native-static/include/SDL3/SDL_mouse.h:298:91: note: passing argument to parameter 'y' here
extern SDL_DECLSPEC SDL_MouseButtonFlags SDLCALL SDL_GetGlobalMouseState(float *x, float *y);
											  ^
2 warnings generated.
[25/75] Compiling C object app/scrcpy.p/src_display.c.o
../../../app/src/display.c:63:29: warning: incompatible pointer types assigning to 'SDL_GLContext *' (aka 'struct SDL_GLContextState **') from 'SDL_GLContext' (aka 'struct SDL_GLContextState *') [-Wincompatible-pointer-types]
	display->gl_context = SDL_GL_CreateContext(window);
			    ^ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~
../../../app/src/display.c:103:35: warning: incompatible pointer types passing 'SDL_GLContext *' (aka 'struct SDL_GLContextState **') to parameter of type 'SDL_GLContext' (aka 'struct SDL_GLContextState *'); dereference with * [-Wincompatible-pointer-types]
	    SDL_GL_DestroyContext(display->gl_context);
				  ^~~~~~~~~~~~~~~~~~~
				  *
/src/scm/android/scrcpy/app/deps/work/install/macos-native-static/include/SDL3/SDL_video.h:3300:70: note: passing argument to parameter 'context' here
extern SDL_DECLSPEC bool SDLCALL SDL_GL_DestroyContext(SDL_GLContext context);
								     ^
../../../app/src/display.c:119:27: warning: incompatible pointer types passing 'SDL_GLContext *' (aka 'struct SDL_GLContextState **') to parameter of type 'SDL_GLContext' (aka 'struct SDL_GLContextState *'); dereference with * [-Wincompatible-pointer-types]
    SDL_GL_DestroyContext(display->gl_context);
			  ^~~~~~~~~~~~~~~~~~~
			  *
/src/scm/android/scrcpy/app/deps/work/install/macos-native-static/include/SDL3/SDL_video.h:3300:70: note: passing argument to parameter 'context' here
extern SDL_DECLSPEC bool SDLCALL SDL_GL_DestroyContext(SDL_GLContext context);
								     ^
3 warnings generated.
[75/75] Linking target app/scrcpy

[rom1v]

Thank you 👍

[metayan]

I had the branch spun off from sdl3 and didn't notice that Github selected master.
Shall I make a new PR to keep it clean?

[rom1v]

No, i'll just integrate the changes into my branch.

[yume-chan]

Shall I make a new PR to keep it clean?

The target branch can be changed by clicking the Edit button

[metayan]

@yume-chan
Excellent.
Thanks.

[rom1v]

I merged your first commit directly into dev, it also applies to SDL2: e47529a
(even if the problem was silently ignored in SDL2)

[rom1v]

I fixed up the other commit into my commit Migrate from SDL2 to SDL3 in #6216.