progs/tests: compile with SCons and glew

Also get mingw cross-compilation of these tests working
diff --git a/progs/tests/debugger.c b/progs/tests/debugger.c
index 4c6955b..1c2f9be 100644
--- a/progs/tests/debugger.c
+++ b/progs/tests/debugger.c
@@ -9,7 +9,7 @@
 #include <stdio.h>
 #include <stdlib.h>
 #include <math.h>
-#define GL_GLEXT_PROTOTYPES
+#include <GL/glew.h>
 #include <GL/glut.h>
 
 
@@ -81,6 +81,7 @@
 #define NV_FRAGMENT_PROGRAM   4
 
 
+
 struct breakpoint {
    enum {PIXEL, LINE} type;
    int x, y;
@@ -101,7 +102,7 @@
 {
    static GLuint skipCount = 0;
    const GLubyte *ln;
-   GLint pos, line, column;
+   GLint pos = 0, line, column;
    GLint id;
    int progType;
    GLint len;
@@ -721,6 +722,7 @@
    glutInitWindowSize( 200, 200 );
    glutInitDisplayMode( GLUT_RGB | GLUT_DOUBLE | GLUT_DEPTH );
    glutCreateWindow(argv[0]);
+   glewInit();
    glutReshapeFunc( Reshape );
    glutKeyboardFunc( Key );
    glutSpecialFunc( SpecialKey );