SDL: minor update to os2 makefile. (binary output doesn't change.)

SDL Commits
1 
From b5b7804ed42b325fa34ea9ef262f7a604334a1b5 Mon Sep 17 00:00:00 2001
From: Ozkan Sezer <[EMAIL REDACTED]>
Date: Sat, 15 May 2021 00:50:20 +0300
Subject: [PATCH] minor update to os2 makefile. (binary output doesn't change.)

---
 Makefile.os2 | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/Makefile.os2 b/Makefile.os2
index 60dd9f6e1..f6fc5c3db 100644
--- a/Makefile.os2
+++ b/Makefile.os2
@@ -62,6 +62,8 @@ SRCS+= SDL_sysloadso.c
 SRCS+= SDL_sysfilesystem.c
 SRCS+= SDL_os2joystick.c SDL_syshaptic.c SDL_sysjoystick.c
 SRCS+= SDL_virtualjoystick.c
+SRCS+= SDL_hidapi.c
+SRCS+= SDL_hidapijoystick.c SDL_hidapi_rumble.c SDL_hidapi_gamecube.c SDL_hidapi_ps4.c SDL_hidapi_ps5.c SDL_hidapi_stadia.c SDL_hidapi_switch.c SDL_hidapi_xbox360.c SDL_hidapi_xbox360w.c SDL_hidapi_xboxone.c SDL_hidapi_steam.c
 SRCS+= SDL_dummyaudio.c SDL_diskaudio.c
 SRCS+= SDL_nullvideo.c SDL_nullframebuffer.c SDL_nullevents.c
 SRCS+= SDL_dummysensor.c
@@ -84,7 +86,7 @@ MOBJS= $(MSRCS:.c=.obj)
 .c: ./src;./src/dynapi;./src/audio;./src/cpuinfo;./src/events;./src/file;./src/haptic;./src/joystick;./src/power;./src/render;./src/render/software;./src/sensor;./src/stdlib;./src/thread;./src/timer;./src/video;./src/video/yuv2rgb;./src/atomic;./src/audio/disk;
 .c: ./src/haptic/dummy;./src/joystick/dummy;./src/joystick/virtual;./src/audio/dummy;./src/video/dummy;./src/sensor/dummy;
 .c: ./src/core/os2;./src/core/os2/geniconv;./src/audio/os2;./src/loadso/os2;./src/filesystem/os2;./src/joystick/os2;./src/thread/os2;./src/timer/os2;./src/video/os2;
-.c: ./src/locale/;./src/locale/unix;./src/misc;./src/misc/dummy
+.c: ./src/locale/;./src/locale/unix;./src/misc;./src/misc/dummy;./src/joystick/hidapi;./src/hidapi
 
 all: $(DLLFILE) $(LIBFILE) .symbolic
 
@@ -123,6 +125,10 @@ SDL_blendpoint.obj: SDL_blendpoint.c
 SDL_RLEaccel.obj: SDL_RLEaccel.c
     wcc386 $(CFLAGS) -wcd=201 -fo=$^@ $<
 
+# c99 mode needed because of structs with flexible array members in libusb.h
+SDL_hidapi.obj: SDL_hidapi.c
+    wcc386 $(CFLAGS) -za99 -I"src/hidapi/hidapi" -fo=$^@ $<
+
 .c: ./src/libm;
 $(LIBM): $(MOBJS)
     wlib -q -b -n -c -pa -s -t -zld -ii -io $@ $(MOBJS)