configure.ac: update the path of the generated files

... in order to determine if we need bison/flex. Failing to locate the
files will lead to mandating bison/flex even when building from a
release tarball.

CC: "11.2" <mesa-stable@lists.freedesktop.org>
Signed-off-by: Emil Velikov <emil.velikov@collabora.com>
Acked-by: Jason Ekstrand <jason@jlekstrand.net>
Reviewed-by: Matt Turner <mattst88@gmail.com>
diff --git a/configure.ac b/configure.ac
index ffd51db..c426c72 100644
--- a/configure.ac
+++ b/configure.ac
@@ -110,10 +110,10 @@
 AC_CHECK_PROG(RM, rm, [rm -f])
 
 AX_PROG_BISON([],
-              AS_IF([test ! -f "$srcdir/src/glsl/glcpp/glcpp-parse.c"],
+              AS_IF([test ! -f "$srcdir/src/compiler/glsl/glcpp/glcpp-parse.c"],
                     [AC_MSG_ERROR([bison not found - unable to compile glcpp-parse.y])]))
 AX_PROG_FLEX([],
-             AS_IF([test ! -f "$srcdir/src/glsl/glcpp/glcpp-lex.c"],
+             AS_IF([test ! -f "$srcdir/src/compiler/glsl/glcpp/glcpp-lex.c"],
                    [AC_MSG_ERROR([flex not found - unable to compile glcpp-lex.l])]))
 
 AC_CHECK_PROG(INDENT, indent, indent, cat)