SDL: minor update to os2 makefile.

From cd7ef24cba6e567fa3dfe1dc6ebb5ad7128ee7e9 Mon Sep 17 00:00:00 2001
From: Ozkan Sezer <[EMAIL REDACTED]>
Date: Mon, 4 Oct 2021 00:32:56 +0300
Subject: [PATCH] minor update to os2 makefile.

---
 Makefile.os2 | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/Makefile.os2 b/Makefile.os2
index aa074de039..560eccfa35 100644
--- a/Makefile.os2
+++ b/Makefile.os2
@@ -127,7 +127,7 @@ SDL_RLEaccel.obj: SDL_RLEaccel.c
 
 # c99 mode needed because of structs with flexible array members in libusb.h
 SDL_hidapi.obj: SDL_hidapi.c
-    wcc386 $(CFLAGS) -za99 -I"src/hidapi/hidapi" -fo=$^@ $<
+    wcc386 $(CFLAGS) -za99 -fo=$^@ $<
 
 .c: ./src/libm;
 $(LIBM): $(MOBJS)