mesa: Silence compiler warnings on Windows.
diff --git a/src/mesa/shader/prog_parameter.c b/src/mesa/shader/prog_parameter.c
index afdd7e5..b302442 100644
--- a/src/mesa/shader/prog_parameter.c
+++ b/src/mesa/shader/prog_parameter.c
@@ -319,6 +319,7 @@
       return (GLint) paramList->ParameterValues[i][0];
    }
    else {
+      GLuint i;
       const GLint size = 1; /* a sampler is basically a texture unit number */
       GLfloat value;
       GLint numSamplers = 0;