glsl: allow GLSL compiler version to be overridden to 1.50

Although GLSL 1.50 compiler support is not available,
this change will allow MESA_GLSL_VERSION_OVERRIDE=150 to be
used while 1.50 support is being developed.

Since no drivers claim 1.50 GLSL support, this change should
only impact Mesa when MESA_GLSL_VERSION_OVERRIDE=150 is set.

Signed-off-by: Jordan Justen <jordan.l.justen@intel.com>
Reviewed-by: Eric Anholt <eric@anholt.net>
Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
diff --git a/src/glsl/builtin_variables.cpp b/src/glsl/builtin_variables.cpp
index ccee774..53c4c51 100644
--- a/src/glsl/builtin_variables.cpp
+++ b/src/glsl/builtin_variables.cpp
@@ -849,6 +849,7 @@
          generate_130_vs_variables(instructions, state, true);
          break;
       case 140:
+      case 150:
          generate_130_vs_variables(instructions, state, false);
          break;
       default:
@@ -1140,6 +1141,7 @@
          generate_130_fs_variables(instructions, state);
          break;
       case 140:
+      case 150:
          generate_140_fs_variables(instructions, state);
          break;
       default: