glsl2: Give the path within src/mesa/ for headers instead of relying on -I.
diff --git a/src/glsl/linker.cpp b/src/glsl/linker.cpp
index 9d53197..a5faff2 100644
--- a/src/glsl/linker.cpp
+++ b/src/glsl/linker.cpp
@@ -78,7 +78,7 @@
 #include "glsl_symbol_table.h"
 #include "ir.h"
 #include "program.h"
-#include "hash_table.h"
+#include "program/hash_table.h"
 #include "linker.h"
 #include "ir_optimization.h"