Increase input_attachment_index limit

The new limit is INT_MAX, as opposed to UINT_MAX, because INT_MAX is
large enough and there are other places in the code where the value of
the limit is cast to int.

Author: rg3igalia

glslang/Include/Types.h

@@ -966,8 +966,8 @@ class TQualifier {
                  unsigned int layoutXfbOffset            : 13;
     static const unsigned int layoutXfbOffsetEnd     = 0x1FFF;
 
-                 unsigned int layoutAttachment           :  8;  // for input_attachment_index
-    static const unsigned int layoutAttachmentEnd      = 0XFF;
+                 unsigned int layoutAttachment;                 // for input_attachment_index
+    static const unsigned int layoutAttachmentEnd = INT_MAX;
 
                  unsigned int layoutSpecConstantId;
     static const unsigned int layoutSpecConstantIdEnd = UINT_MAX;