mesa: fix vertex program test in get_fp_input_mask()

We were accidentally using the fixed-function logic when a vertex shader was
being used.

src/mesa/main/texenvprogram.c

@@ -215,9 +215,7 @@ static GLbitfield get_fp_input_mask( GLcontext *ctx )
    else if (ctx->RenderMode == GL_FEEDBACK) {
       fp_inputs = (FRAG_BIT_COL0 | FRAG_BIT_TEX0);
    }
-   else if (!ctx->VertexProgram._Enabled ||
-            !ctx->VertexProgram._Current) {
-
+   else if (!ctx->VertexProgram._Current) {
       /* Fixed function logic */
       GLbitfield varying_inputs = ctx->varying_vp_inputs;