Fix Shell MTRR print issue

Current MTRR lib assumes the MTRR number is always 10. Instead,
this patch follows the IA manual to get the actual MTRR number
through MTRR capability register.

Signed-off-by: Maurice Ma <maurice.ma@intel.com>

BootloaderCommonPkg/Library/MtrrLib/MtrrLib.c

@@ -9,6 +9,7 @@ SPDX-License-Identifier: BSD-2-Clause-Patent
 #include <Library/BaseLib.h>
 #include <Library/DebugLib.h>
 #include <Library/ConsoleOutLib.h>
+#include <Register/Intel/ArchitecturalMsr.h>
 
 /**
   Convert the MTRR memory type to a readable str
@@ -67,6 +68,7 @@ PrintMtrr (
   UINT64      Mask;
   UINT64      Range;
   UINT64      Limit;
+  MSR_IA32_MTRRCAP_REGISTER MtrrCap;
 
   if (Str != NULL) {
     CONSOLE_PRINT_CONDITION (ConsoleOut, (DEBUG_INFO, "%a\n", Str));
@@ -85,7 +87,8 @@ PrintMtrr (
 
   // Dump Variable MTRR registers
   CONSOLE_PRINT_CONDITION (ConsoleOut, (DEBUG_INFO, "Variable MTRRs\n"));
-  for (Index = 0; Index < 10; Index++) {
+  MtrrCap.Uint64 = AsmReadMsr64 (MSR_IA32_MTRRCAP);
+  for (Index = 0; Index < MtrrCap.Bits.VCNT; Index++) {
     BaseMsr = 0x200 + (Index * 2);
     MaskMsr = BaseMsr + 1;