CorebootModulePkg: Fix build failure with 32-bit NOOPT target

Fix build failure with 32-bit NOOPT target by replacing direct shift
of 64-bit integer with a function call. Otherwise Microsoft tool chains
will generate a call to function __allshl and fail to link.

Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Scott Duplichan <scott@notabs.org>
---

Index: CorebootModulePkg/Library/CbParseLib/CbParseLib.c
===================================================================
--- CorebootModulePkg/Library/CbParseLib/CbParseLib.c	(revision 17108)
+++ CorebootModulePkg/Library/CbParseLib/CbParseLib.c	(working copy)
@@ -28,7 +28,7 @@
 
 static UINT64 cb_unpack64(struct cbuint64 val)
 {
-  return (((UINT64) val.hi) << 32) | val.lo;
+  return LShiftU64 (val.hi, 32) | val.lo;
 }
 
 static const char *cb_mb_vendor_string(const struct cb_mainboard *cbm)