loader: use generated dispatch table ops

This also fixes several typos in xglGetProcAddr(), such as in

    else if (!strncmp("xglCreateFence", pName, sizeof ("xgllCreateFence")))
        return disp_table->CreateFence;

They are generally harmless though.
diff --git a/.gitignore b/.gitignore
index fbe7584..ce64764 100644
--- a/.gitignore
+++ b/.gitignore
@@ -9,6 +9,7 @@
 icd/common/libicd.a
 icd/intel/intel_gpa.c
 loader/dispatch.c
+loader/table_ops.h
 tests/xgl_image_tests
 tests/xgl_render_tests
 tests/xglbase