GWN: Perf: Bypass glUseProgram(0)

I left a flag to quickly debug if something is wrong.
But now that everything uses shader, it seems to be alright since a shader
is always set active before drawing.

intern/gawain/gawain/gwn_common.h

@@ -11,6 +11,8 @@
 
 #pragma once
 
+#define PROGRAM_NO_OPTI 0
+
 #if defined(NDEBUG)
   #define TRUST_NO_ONE 0
 #else

intern/gawain/src/gwn_batch.c

@@ -418,7 +418,9 @@ void GWN_batch_program_use_end(Gwn_Batch* batch)
 	{
 	if (batch->program_in_use)
 		{
+#if PROGRAM_NO_OPTI
 		glUseProgram(0);
+#endif
 		batch->program_in_use = false;
 		}
 	}

intern/gawain/src/gwn_immediate.c

@@ -140,8 +140,9 @@ void immUnbindProgram(void)
 #if TRUST_NO_ONE
 	assert(imm.bound_program != 0);
 #endif
-
+#if PROGRAM_NO_OPTI
 	glUseProgram(0);
+#endif
 	imm.bound_program = 0;
 	}