[PATCH v2] OvmfPkg/QemuBootOrderLib: Fix NOOPT build failure

[Dandan Bi <dandan.bi@intel.com>]

This patch is to fix the IA32/NOOPT/VS Toolchain build failure.

Cc: Jordan Justen <jordan.l.justen@intel.com>
Cc: Laszlo Ersek <lersek@redhat.com>
Cc: Liming Gao <liming.gao@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Dandan Bi <dandan.bi@intel.com>

Notes:
  V2: Change the cast type form UINT32 to UINTN.
      Add commit message to cover the impacted Arch/Toolchain.
---
 OvmfPkg/Library/QemuBootOrderLib/ExtraRootBusMap.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/OvmfPkg/Library/QemuBootOrderLib/ExtraRootBusMap.c b/OvmfPkg/Library/QemuBootOrderLib/ExtraRootBusMap.c
index ec42214..70ba161 100644
--- a/OvmfPkg/Library/QemuBootOrderLib/ExtraRootBusMap.c
+++ b/OvmfPkg/Library/QemuBootOrderLib/ExtraRootBusMap.c
@@ -306,8 +306,8 @@ MapRootBusPosToBusNr (
     return EFI_INVALID_PARAMETER;
   }
   if (RootBusPos > ExtraRootBusMap->Count) {
     return EFI_NOT_FOUND;
   }
-  *RootBusNr = ExtraRootBusMap->BusNumbers[RootBusPos - 1];
+  *RootBusNr = ExtraRootBusMap->BusNumbers[(UINTN)RootBusPos - 1];
   return EFI_SUCCESS;
 }
-- 
1.9.5.msysgit.1