intel: Add shader resource urb_read_offset

The urb_read_offset is used by 3DSTATE_VS.
Right now just set it to "safe" default value.
diff --git a/icd/intel/shader.c b/icd/intel/shader.c
index 4880039..9511ecd 100644
--- a/icd/intel/shader.c
+++ b/icd/intel/shader.c
@@ -53,6 +53,7 @@
         sh->in_count = 1;
         sh->out_count = 2;
         sh->urb_grf_start = 1;
+        sh->urb_read_length = 1;
         break;
     case 'w':
         sh->out_count = 1;